ACUS01 KWNS 051948
SWODY1
SPC AC 051946

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0146 PM CST Fri Mar 05 2021

Valid 052000Z - 061200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EAST
CENTRAL INTO SOUTHEAST TEXAS AND FAR SOUTHWEST LOUISIANA...

...SUMMARY...
A few thunderstorms capable of producing hail and gusty winds may
develop this afternoon over portions of east-central through
southeast Texas and far southwest Louisiana.

...Discussion...
No appreciable change was made to the previous convective outlook.

..Smith.. 03/05/2021

.PREV DISCUSSION... /ISSUED 1030 AM CST Fri Mar 05 2021/

...East central through southeast Texas...

As of late morning a cold front stretches from a surface low near
Gainesville, south southwestward through east central and south TX.
A warm front extends from the northwestern Gulf into southeast and
south central TX. Partially modified Gulf air with upper 50s to near
60 F dewpoints reside in the warm sector. Visible imagery still
indicates widespread low and mid-level clouds in pre-frontal zone,
but some of these clouds should mix out from the south and west
resulting in a narrow corridor of modest surface heating which
should boost MLCAPE to near 500 J/kg from east central into
southeast TX and possibly far southwest LA. Deeper forcing attending
a vorticity maximum embedded within a cutoff upper low circulation
will move from northwest TX into east central and southeast TX this
afternoon. This should foster thunderstorm development along and
east of the cold front later today. Though winds increase
substantially above 5 km, the anticipated relatively shallow
convective layer should limit effective bulk shear to between 30 and
40 kt. A few cells might develop weak mid-level updraft rotation and
when combined with 7 C/km mid-level lapse rates and modest
instability, could pose some risk for hail. Some clustering of
storms is possible and a few locally strong wind gusts might occur
before activity moves offshore this evening. Overall threat should
remain limited by the marginal thermodynamic environment.

$$
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ACUS01 KWNS 062000
SWODY1
SPC AC 061959

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0159 PM CST Sat Mar 06 2021

Valid 062000Z - 071200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE EAST
COAST OF SOUTH FLORIDA...

...SUMMARY...
A few strong to locally severe thunderstorms are possible through
the late afternoon near the east coast of south Florida.

...Discussion...
Other than the removal of low-severe probabilities near the Space
Coast in FL, the forecast remains largely unchanged and on track.
See the previous convective outlook for details.

..Smith.. 03/06/2021

.PREV DISCUSSION... /ISSUED 1030 AM CST Sat Mar 06 2021/

...Central/southern Florida Peninsula...
Thunderstorms have developed and increased across the north-central
Florida Peninsula. In spite of weak mid-level lapse rates,
relatively long hodographs accentuated by strong mid-level
westerlies atop east-northeasterly boundary layer winds, coincident
with modest but sufficient buoyancy, could support a few additional
strong to locally severe storms this afternoon across the
east-central Florida Peninsula.

Farther south in a somewhat more moisture-rich air mass, additional thunderstorm development is expected later this afternoon,
particularly across the near-coastal southeast Peninsula. This will
be coincident with relatively long hodographs (35-45 kt effective
shear) and upwards of 500-800 J/kg MLCAPE, which will be potentially
supportive of a few strong to locally severe storms.

$$
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ACUS01 KWNS 141952
SWODY1
SPC AC 141951

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Sun Mar 14 2021

Valid 142000Z - 151200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THROUGH THIS
EVENING FROM NORTHEAST CO INTO NORTHWEST KS AND SOUTHWEST NE...AND
LATER TONIGHT ACROSS PARTS OF THE LOWER MS VALLEY...

...SUMMARY...
Isolated severe thunderstorms are possible across a part of
northeast Colorado, northwest Kansas and southwest Nebraska through
early evening, and across a portion of the Lower Mississippi Valley
tonight.

...20z Update - CO/KS/NE...

The Marginal risk area has been shifted west/southwest this
afternoon. This is based on current surface observations and visible
satellite imagery. A surface low is located north of LAA and
southwest of ITR with an occluded front extending from the low
north/northeast a near the KS/NE border. Strong surface heating in
the vicinity of this boundary has resulted in weak destabilization
this afternoon and isolated thunderstorms have developed along the
boundary and near the surface low. Marginal hail will be possible
with this activity given steep midlevel lapse rates and moderate
shear. Low level shear will remain enhanced near the boundary, and a
funnel cloud has already been reported with a cell in Hitchcock
County NE. Brief funnels or even a weak tornado will remain possible
the next few hours. For more details, reference MCD 177.

Otherwise, the remainder of the outlook remains on track and no
other changes were made except to adjust 10% general thunder in line
with current observations.

..Leitman.. 03/14/2021

.PREV DISCUSSION... /ISSUED 1122 AM CDT Sun Mar 14 2021/

...Lower MS Valley...
A deep, occluded low over eastern CO will slowly fill as it drifts
east into western KS through tonight. An embedded mid-upper jet
streak will rotate around the southeastern periphery of the low,
in conjunction with a Pacific cold front moving from eastern OK/TX
into AR/LA by this evening. Only meager convection has been noted
this morning in the band of ascent along and behind the front. This
may continue through much of the period as a result of paltry
warm-sector buoyancy, as well as a capping inversion around 700 mb
in 12Z soundings from CRP-SHV-LZK. Still, conditional potential for
a tornado or isolated strong wind gust exists tonight as mid 60s
surface dew points spread toward the Ark-La-Miss and mid-level temps
slightly cool. This may result in a small corridor of spatiotemporal
overlap with 250-500 J/kg MLCAPE and a moderately enlarged low-level
hodograph.

...Northwest/north-central KS to southwest NE...
A narrow corridor of low-topped surface-based convection might
develop during the late afternoon to early evening along a
convergent occluded front where a plume of 40s surface dew points
can be maintained. Here, surface heating beneath rather cold
mid-level temperatures should result in steep low to mid-level lapse
rates. Low probabilities are maintained for marginally severe hail
along with a brief tornado from a cell or two.

$$
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ACUS01 KWNS 151950
SWODY1
SPC AC 151949

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Mon Mar 15 2021

Valid 152000Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER
MO VALLEY AND MS/AL...

...SUMMARY...
Isolated severe storms are possible across parts of Alabama and
Mississippi through tonight. Isolated severe storms are also
possible from east-central Kansas through central Missouri through
early evening.

...20z Update...

The ongoing outlook remains on track and no changes are needed with
this update. Reference MCD 180 for short-term severe threat across
MS/AL, and MCD 181 for the short-term severe threat across KS/MO.

..Leitman.. 03/15/2021

.PREV DISCUSSION... /ISSUED 1130 AM CDT Mon Mar 15 2021/

...MS/AL...
A low-confidence severe threat remains apparent across the region
through tonight. A band of predominantly low-topped showers is
ongoing from northwest AL to southwest MS along a weakening surface
cold front, to the south of an embedded shortwave impulse advancing
north across the Mid-MS Valley. While further frontolysis is
expected, some of this convective activity should persist through
the afternoon and become more west/east-oriented across
northern/central AL and central MS. Broken cloudiness out ahead of
this activity will support further boundary-layer heating amid mid
60s dew points from the western half of AL to the southwest.
Low-level wind profiles should slowly weaken and become more veered
with western extent. The conditional threat for a supercell or two
during the late afternoon to early evening may be focused across the west-central AL vicinity where all hazards would be possible. Still,
given the poor forcing for large-scale ascent, probabilities remain
too low to warrant an upgrade this outlook. Otherwise, additional
convection may form overnight within a weak low-level warm advection
regime to the north of the central Gulf Coast. Rich low-level
moisture and continued strong deep-layer shear may support a
low-probability severe threat.

...East-central KS to central MO...
The deep closed low over central KS will evolve into an open wave
and eject east-northeast across the Midwest through tonight, in
response to upstream height falls with a strong shortwave trough
digging across CA. Though the richer low-level moisture is confined
to the Lower MS Valley, lingering boundary-layer dewpoints in the
mid to upper 40s are prevalent within the northern extent of robust
insolation across southeast KS and southwest MO. Beneath cold
mid-level temperatures, the steep-lapse-rate environment will
support meager MLCAPE approaching 500 J/kg in a corridor east of the
surface cyclone and along a stalled front in central MO.

Within the left-exit region of a strengthening mid-level jet,
isolated to scattered thunderstorms are expected to form by mid
afternoon in the zone of ascent near/east of the surface low towards
the KS/MO border, with successive development of storms eastward
into central MO through early evening. Wind profiles, especially
with eastern extent in central MO, should support a couple
low-topped supercells with effective bulk shear of at least 30 kt
and some hodograph curvature in the low levels. Marginally severe
hail, isolated damaging gusts, and a tornado will be possible with
storms along the boundary this afternoon/evening. The bulk of
convection should generally propagate further across the cool side
of the front, where low-level stratus will likely remain pervasive,
and become elevated before weakening later this evening.

$$
--- SBBSecho 3.12-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (618:250/1)

ACUS01 KWNS 182127
SWODY1
SPC AC 182126

Day 1 Convective Outlook AMEND 1
NWS Storm Prediction Center Norman OK
0426 PM CDT Thu Mar 18 2021

Valid 182000Z - 191200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
SOUTH CAROLINA THROUGH CENTRAL AND EASTERN NORTH CAROLINA AND
SOUTHEAST VIRGINIA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE SOUTHERN APPALACHIANS AND A PORTION OF NORTHERN FLORIDA...

AMENDED FOR TO EXPAND ENHANCED RISK FARTHER NORTH INTO SOUTHEAST
VIRGINIA FOR TORNADO AND DAMAGING WIND THREAT

...SUMMARY...
Scattered severe storms remain possible this afternoon and evening
mainly from a portion of South Carolina through central and eastern
North Carolina and southeast Virginia. Other strong to severe storms
are possible this afternoon over the southern Appalachian region as
well as northern Florida.

...South Carolina through central and eastern North Carolina and
southeast Virginia...

Cluster of storms over western SC and southwestern NC is expected to
continue developing northeast through central and eventually eastern
NC this afternoon and evening. Vertical wind profiles with 50+ kt
effective bulk shear and sizeable 0-2 km hodographs will remain
supportive of organized severe storms including supercells. However,
trend has been for a pocket of dry air in the low levels to advect
northward through northern SC into southeastern NC, and this has at
least temporarily reduced boundary layer instability. Nevertheless,
some low-level theta-e advection will resume in wake of the dry
pocket contributing to 1000-1500 J/kg MLCAPE. The best chance for
severe storms are expected as activity develops northeast along
instability gradient through a portion of central and eastern NC and
possibly southeast VA this afternoon and evening with damaging wind,
large hail and a few tornadoes possible.

...Southern Appalachian region...

Storms are developing within corridor of ascent just east of the
progressive shortwave trough. Cold temperatures aloft, steep lapse
rates and diabatic heating will continue to foster widely scattered
storm development this afternoon. Isolated large hail and a few
locally strong wind gusts are the main threats. Activity should
diminish toward late afternoon or early evening.

..Dial.. 03/18/2021

.PREV DISCUSSION... /ISSUED 1133 AM CDT Thu Mar 18 2021/

...Southeast...
Overall severe threat will likely focus in two corridors which are
encompassed by the cat 3/ENH risk for tornado and wind. Initial
broken band of non-severe convection is ongoing from south-central
GA through the eastern FL Panhandle. This activity has struggled to
intensify despite strong low to deep-layer shear as it impinges on a
relative minimum in buoyancy sampled by the 12Z JAX sounding and
evident in mesoanalysis time-series. However, destabilization is
occurring downstream from north FL to the coastal Carolinas and
redevelopment of severe storms is anticipated at some point this
afternoon. The eastward translation of a 50-55 kt LLJ will support
an enlarged hodograph favorable for a few supercells. Modest
mid-level lapse rates will remain a limiting factor, though MLCAPE
will be large enough given to support a few tornadoes and scattered
damaging winds, with a strong tornado or two still possible.

The separate area of potential severe should be coincident with the
track of a mesolow from the northeast GA/northwest SC border across
the Piedmont towards south-central VA. Here, MLCAPE will likely
remain weak but cloud breaks just ahead of the low near the
mid-level dry slot may prove sufficient for an intensifying area of
convection. Where sufficient buoyancy overlaps the more
favorable/curved hodographs east of the mountains, a couple
supercells capable of a strong tornado, damaging winds, and isolated
large hail will all be possible this afternoon/evening.

...OH Valley...
East and southeast of the weakening occluded cyclone, pockets of
stronger boundary-layer heating are underway on the nose of the
mid-level dry slot. In conjunction with cool mid-level temperatures,
500-1000 J/kg of MLCAPE will be sufficient for a few strong-severe
storms later this afternoon. This area will be on the northwest edge
of the stronger flow/shear, where a mix of multicell clusters and a
few low-end supercells are probable. A tornado or two, large hail,
and damaging winds will be possible.

$$
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ACUS01 KWNS 251246
SWODY1
SPC AC 251245

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 AM CDT Thu Mar 25 2021

Valid 251300Z - 261200Z

...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS WITH A TORNADO
OUTBREAK EXPECTED ACROSS PARTS OF NORTHERN MISSISSIPPI...NORTHERN
ALABAMA...AND SOUTHERN TENNESSEE...

...SUMMARY...
A tornado outbreak -- including the threat of a few long-tracked,
violent tornadoes -- is expected today into early this evening over
the Southeast, especially parts of Mississippi, Alabama and
Tennessee. Tornadoes, large to very large hail, and damaging winds
to hurricane force also are possible over a broad area from the
central Gulf Coast to the Ohio Valley and southern Appalachians.

--- Technical Discussion ---

...Synopsis...
In mid/upper levels, a longwave trough will be maintained over the
western CONUS, as a strong shortwave trough and related speed max
dig south-southeastward across the interior Northwest, and a
formerly basal trough ejects northeastward. The latter trough is
evident in moisture-channel imagery over the southern High Plains to
the Big Bend region of TX, and will move to MO/AR by 00Z. By 12Z,
this feature should reach Lake Erie and OH. This trough will pack
the height gradient to its southeast enough to yield 110-130-kt
250-mb flow and 80-100-kt 500-mb winds over much of the Mid-South,
and Tennessee/Ohio Valleys today and this evening.

The associated surface low-pressure area was analyzed at 11Z across
western AR to northwestern LA, still poorly consolidated around
areas of rain-cooled air. A cold front was drawn from northwestern
LA across southeast TX the middle TX Coast and deep south TX. A
"synoptic" warm front arched from the low-pressure

ACUS01 KWNS 270553
SWODY1
SPC AC 270551

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1251 AM CDT Sat Mar 27 2021

Valid 271200Z - 281200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
ARKANSAS TO MIDDLE TENNESSEE...

...SUMMARY...
Severe storms are expected across the lower Mississippi through
Tennessee Valley regions. All hazards are possible including very
large hail, damaging wind, and tornadoes. Potential for a strong
tornado exists from eastern Arkansas into western Tennessee. Other
severe storms are possible across a portion of the Midwest with
isolated damaging wind and large hail the main threats.

...Lower MS Valley/TN Valley...

Large-scale heights will not change appreciably until late in the
day1 period across the lower MS and TN Valley region. Water-vapor
imagery depicts an upper low digging southeast across AZ early this
morning. This feature is forecast to translate across far West TX
during the evening before deamplifying as it ejects into
north-central TX late. Prior to the influence of this feature, one
LLJ branch will extend across the TX Coast-LA-middle TN. Low-level
warm advection in association with this feature is expected to
encourage a considerable amount of convection that should be ongoing
at the start of the period. Several members of the HREF suggest a
possible MCS may evolve over middle TN, then propagate east during
the day. Areal extent of this activity may greatly influence
convective development later in the day as rain-cooled boundary
layer may establish an outflow boundary that could drape west across
TN.

Strongest low-level heating will be noted south of this rain-cooled
air mass, and buoyancy should be greatest from northeast TX into
northern MS where SBCAPE will exceed 2000-2500 J/kg. With
temperatures warming into the mid-upper 70s, it appears surface
parcels will reach their convective temperatures by 20z and
scattered discrete storms will likely develop from the Arklatex,
northeast toward the early-day outflow boundary over western TN.
This corridor will likely experience significant convective coverage
by the end of the period.

Forecast wind profiles favor supercells and lapse rates should be
sufficiently steep for very large hail with storms across the
western half of the ENH Risk. Tornadoes are also possible, a few
potentially strong, with discrete storms, though QLCS-type spin ups
are also possible as a squall line matures later in the evening. As
the squall line matures, the threat for strong, damaging winds will
become more likely as deep-layer westerly flow increases across the
mid-South Region.

Farther north, strong mid-level height falls will overspread the
upper Midwest region in advance of a northern branch short-wave
trough that will dig into WI/IA/MO by 28/12z. It's not entirely
clear how much moisture/instability will be drawn north ahead of the
surface low into eastern MO/IL prior to convective initiation. 00z
NAM suggests mid 50s surface dew points will advance across this
region which will help destabilization; however, nearest mid 50s
surface dew points are roughly 300 mi south across southeast
AR/northern MS. If early-day convection disrupts this moisture flow,
then somewhat less buoyancy may be available for convection
extending ahead of the low into central IL. At this time wind/hail
appear to be the primary risks with robust storms along the front.

..Darrow/Dean.. 03/27/2021

$$
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ACUS01 KWNS 271957
SWODY1
SPC AC 271955

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Sat Mar 27 2021

Valid 272000Z - 281200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
INTO TONIGHT FROM PARTS OF THE ARK-LA-TEX ACROSS THE MID SOUTH AND
TN VALLEY...

...SUMMARY...
Severe storms are likely this afternoon into tonight from the
Ark-La-Tex east-northeastward across parts of the Mid South and
Tennessee Valley. All hazards are possible including very large
hail, significant damaging winds, and a couple of strong tornadoes.

Only minor changes have been made to adjust for the ongoing cluster
of storms moving east across North Carolina. Elsewhere, the forecast
remains on track. See the previous discussion for more details.

..Wendt.. 03/27/2021

.PREV DISCUSSION... /ISSUED 1124 AM CDT Sat Mar 27 2021/

...Mid South/TN Valley region through tonight...
Elevated convection with a marginal hail threat that formed
overnight in a zone of warm advection, along and north of the
surface warm front from the Mid South into middle/eastern TN,
persists as of late morning. The convection is also associated with
a subtle mid-upper speed max moving east-northeastward over the Mid
South. Farther west, additional storm development is expected by
early-mid afternoon along the rain-reinforced front close to the
MS/AL/TN border region. This afternoon convection will likely be
rooted at the surface as the low levels continue to warm/moisten
from the south, with a few supercells possible with MLCAPE near 2000
J/kg, effective bulk shear near 50 kt, and effective SRH around 150
m2/s2.

Farther west into northeast TX and southern/eastern AR,
surface-based supercell development is expected by mid afternoon
along the moisture gradient/warm front, as the low levels continue
to destabilize and the cap weakens. The forcing for ascent will be
rather subtle, so the primary storm mode should be a mix of discrete
supercells and clusters moving east-northeastward along the buoyancy gradient/front this afternoon into early tonight. Isolated very
large hail, damaging winds, and a couple of tornadoes will be the
main concerns this afternoon. Some increase in low-level shear is
expected this evening, which will support an increase in the tornado
threat, with an isolated strong tornado or two possible. Otherwise,
storms overnight should consolidate into more of a solid band as the
synoptic cold front overtakes the convection from the northwest, in
response to phasing of the northern and southern streams, with
cyclogenesis from IL to Lower MI.

...Eastern OK/northwestern AR to IL this afternoon/evening...
The primary surface cyclone is expected to begin deepening this
evening across IL, before moving to Lower MI overnight. In the wake
of the low, a cold front will begin to accelerate southeastward
later this evening into tonight. The primary uncertainties along
this corridor are the degree of low-level
moistening/destabilization, and the magnitude of the low-level
shear. The main low-level mass response/low-level jet will likely
be directed into the rather persistent zone of convection farther to
the southeast along the effective warm front from northeast TX to
western TN. These factors suggest substantial limitations to the
wind/hail threat along the cold front farther to the northwest, with
the most questionable area centered on northwestern AR.

...Carolinas this afternoon/evening...
The cluster of storms in eastern TN has been elevated through the
morning, but some northward expansion of the surface warm sector is
expected through this afternoon from SC into NC. Given sufficient
deep-layer vertical shear, an organized cluster with some threat for
damaging winds/large hail may persist into the afternoon along the
warm front from the Piedmont eastward across NC and adjacent
portions of SC.

$$
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ACUS01 KWNS 280556
SWODY1
SPC AC 280555

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Sun Mar 28 2021

Valid 281200Z - 291200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS
SOUTHEASTERN VIRGINIA AND ADJACENT FAR NORTHEAST NORTH CAROLINA...

...SUMMARY...
Scattered severe storms are likely along an advancing cold front
from the Mid-Atlantic into the Carolinas. The highest confidence in
damaging winds is in southeastern Virginia and vicinity. Farther
south and west, a few strong to severe storms are possible from
Mississippi into Georgia.

...Synopsis...
Shortwave trough currently extending from the Upper Midwest back
southwestward through the central Plains will continue eastward
throughout the day, moving through the Great Lakes, OH Valley,
Mid-Atlantic and much of the Northeast. As it does, the system is
expected to mature significantly, with both a deep surface low over
southern Quebec and strong mid-level flow from the TN Valley into
the Mid-Atlantic predicated by this afternoon.

A cold front will also accompany this system. Expectation is for
this front to extend from western NY southwestward along the central
and southern Appalachians by around 18Z this afternoon. The front is
forecast to be off the Northeast and Mid-Atlantic coasts by 00Z
Monday. A broad area of at severe potential will exist of this front
from the northern Mid-Atlantic into the Southeast.

...Mid-Atlantic/Carolinas...
Ongoing convective system over the TN and Lower MS Valleys is
expected to continue eastward/northeastward this morning and into
this afternoon. Most of the 00Z guidance is too slow with the
forward progression of the system, particularly the portion entering
middle TN, where more forward propagation has been noted. While some
slowing of convective line is likely has instability wanes with
eastern extent, overall expectation is for this area of convection
to reach central VA/NC this morning.

As such, severe potential across the region will be tied to the
potential for re-development along the front. The bulk of the
guidance suggests destabilization will occur ahead of the front, and
that a strongly forced line will develop along the front. Intense
low to mid-level flow will favorable strong, convectively enhanced
wind gusts within this line. A few embedded tornadoes are possible
as well.

Given this severe potential, 30% wind/5% probabilities will be
maintained with this outlook. However, uncertainty regarding the
stability of the air mass preceding the front merits close
observation of overnight trends and guidance, with potential
downgrades needed in subsequent outlooks.

...Southeast...
Modest buoyancy will continue to promote thunderstorm development
along the front as it moves across the region this morning and into
this afternoon. Low-level winds will likely veer before frontal
passage and stronger flow aloft will be increasingly displaced
north. However, the environment will remain conducive to
occasionally organized storms capable of strong downbursts. A brief
tornado or two could also occur within the line, particularly over
northern GA where low-level flow is expected to remain strong as the
line moves through.

..Mosier/Karstens.. 03/28/2021

$$
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ACUS01 KWNS 301559
SWODY1
SPC AC 301557

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1057 AM CDT Tue Mar 30 2021

Valid 301630Z - 311200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
AND TONIGHT FROM THE ARKLATEX REGION INTO THE TENNESSEE VALLEY....

...SUMMARY...
Thunderstorms are expected to develop across the ArkLaTex region and
lower Mississippi through Tennessee Valleys, mainly late this
afternoon and tonight, with isolated strong/severe thunderstorms
possible.

...Arklatex into the Tennessee Valley...
Morning water vapor loop shows a broad upper trough across the
northern Plains and Rockies, with moderately strong
west-southwesterly flow aloft extending from TX into the southeast
states. A cold front is pushing southeastward across OK/MO and will
move into the Arklatex and TN Valleys tonight. Southerly low-level
winds ahead of the front will help to moisten/destabilize the
region, with dewpoints in the 60s and MUCAPE values of 500-1000 J/kg
this evening and tonight. This will lead to a rather broad area of
scattered thunderstorm potential. 12z CAM solutions generally agree
in isolated coverage of storms, and suggest that weak large-scale
forcing will limit the overall updraft/downdraft intensities.
However, forecast soundings show profiles generally favorable for
the risk of hail and gusty winds in the stronger cells that can
develop. Therefore, will maintain the broad MRGL risk category at
this time.

..Hart/Lyons.. 03/30/2021

$$
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ACUS01 KWNS 111259
SWODY1
SPC AC 111258

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0758 AM CDT Sun Apr 11 2021

Valid 111300Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS TODAY OVER
CENTRAL FLORIDA...

...SUMMARY...
The main severe-thunderstorm threat today will be over portions of
the Florida Peninsula, with damaging wind and occasional hail
possible. A tornado cannot be ruled out as well.

...Synopsis...
The mid/upper level pattern will continue to feature split flow
across central North America, but with some shift in the location
and amplitude of the splitting. That mainly will be related to two
features:
1. A cyclone now centered near the IL/IN state line, and forecast
to gradually shrink/fill as its circulation center crosses IN and
northern OH through the period.
2. An initially open-wave, neutral-tilt trough over SK, eastern MT
and northern WY, which will evolve into a closed cyclone as it
crosses the northern Great Plains today. By 12Z tomorrow, the
500-mb low should be near the SD/ND/MN border confluence, along a
trough oriented west-northwest to east-southeast.

In the southern peripheral cyclonic flow of the leading upper low,
two small but important shortwave troughs are apparent: the first a convectively enhanced vorticity lobe over the northeastern Gulf
south of the FL Panhandle, and the second upstream across southeast
TX and LA. These perturbations will proceed eastward across
central/northern FL and the central northeast Gulf Coast regions
through 00Z, with the trailing one crossing northern/central FL
tonight.

At the surface, 11Z analysis showed a primary occluded low over
northern IL, with another near a triple point over northern Lower
MI. A cold front extended from there across eastern OH, to the TRI
and MOB areas, and across the northwestern Gulf. The surface low
(or lows, in a broad cyclone with more than one center possible)
should meander around the states bordering Lake Michigan through the
period. Another cold front associated with the northern Plains
upper trough should move southeastward over the northern/central
Plains and southern High Plains. The cold front related to the
Great Lakes cyclone will shift southeastward over the Carolinas, GA
and northern FL, where convective processes will be largely
prefrontal.

...FL...
Scattered to numerous thunderstorms are expected to evolve from the
ongoing, initially loosely organized activity over the northeastern
Gulf. The resulting convection should sweep across and down the
peninsula today in an increasingly organized, largely forward-
propagational MCS. The main threat will be damaging gusts, some
severe, and a tornado or two cannot be ruled out. (See SPC severe
thunderstorm watch 91 and related mesoscale discussions for
near-term situational coverage.) The main threat area, with
greatest concentration of severe-wind potential, currently appears
to be portions of central and perhaps south-central FL that
experience longer-duration diurnal heating and sustained moisture advection/transport ahead of the complex.

Veering flow with time is expected in much of the pre-MCS boundary
layer, and should have these influences:
1. Making deep-layer winds more unidirectional, with the mean-wind
and deep-shear vectors assuming substantial component along the
convective axis, thereby supporting denser, quasi-linear
configuration,
2. Reducing low-level shear and hodograph size somewhat (but not
enough to forbid QLCS tornado potential entirely) and
3. Advecting higher-theta-e Gulf air across the central/southern
peninsula, supporting potential MLCAPE of 1500-2000 J/kg.

The complex should reach South FL this evening at the latest, and
may affect portions of the Keys as well. Mesoscale trends as the
MCS and its cold-pool/pressure perturbation evolves likely will
compel further extension or adjustment of the probabilities today.

...Mid-Atlantic region...
Widely scattered thunderstorms may develop this afternoon, mainly
along and east of a surface prefrontal/lee trough, moving eastward
to northeastward over the outlook area. Isolated damaging gusts
and/or marginally severe hail are possible.

For generating buoyancy, diurnal destabilization of the boundary
layer behind the morning clouds/precip will help to offset some
relatively weak midlevel lapse rates, along with surface dew points
commonly in the 50s to low 60s north, low/mid 60s south. Depending
on the duration of heating, some mixing-related reduction in surface
moisture is possible, tempering CAPE somewhat, but at the same time,
yielding more evaporation-favoring subcloud layers for localized
acceleration of downdrafts. Peak MLCAPE in the 500-1000 J/kg range
is possible -- locally higher in the southern parts. The main
factor precluding a better-organized threat will be lack of
substantial vertical shear, with only 25-35-kt effective-shear
magnitudes expected (also locally/briefly greater).

..Edwards/Broyles.. 04/11/2021

$$
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ACUS01 KWNS 171232
SWODY1
SPC AC 171231

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0731 AM CDT Sat Apr 17 2021

Valid 171300Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE
GULF COAST STATES...

...SUMMARY...
Isolated severe hail is possible over Deep South Texas this morning.
Isolated severe hail and damaging winds are possible across portions
of the central Gulf Coast through north Florida, mainly during the
late afternoon and evening.

...Central Gulf Coast to north FL...
A quasi-stationary front remains ensconced across far southern LA to north-central FL. A leading swath of convection driven by low-level
warm advection is ongoing along and north of the FL portion of the
front and this should push east off the South Atlantic Coast by
midday. The next round of elevated convection should develop across
the northern Gulf later this morning and spread east-northeast
across the northeast Gulf Coast region this afternoon into this
evening. Mid-level lapse rates will remain weak, yielding primarily
thin elevated buoyancy, but mid-level flow will remain strong,
contributing to favorable vertical shear for the threat of isolated
severe storms. Primary threat will be marginal hail, although a
damaging wind gust or two may be able to penetrate the relatively
shallow low-level stability. Some northward retreat of the surface
front may support convection containing surface-based effective
inflow parcels across north FL this evening.

...Deep South TX...
A few post-frontal elevated thunderstorms are ongoing across the
Lower Rio Grande Valley and should spread into the northwest Gulf
later this morning. Individual cells have repeatedly weakened over
the past few hours despite 500-1200 J/kg of thin effective-layer
CAPE amid 60-70 kt effective shear per the 12Z Brownsville and
Corpus Christi soundings. Nevertheless, the environment suggests a
discrete supercell producing severe hail is still possible through
midday.

..Grams/Broyles.. 04/17/2021

$$
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ACUS01 KWNS 180516
SWODY1
SPC AC 180514

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1214 AM CDT Sun Apr 18 2021

Valid 181200Z - 191200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR CENTRAL
FLORIDA...

...SUMMARY...
Isolated strong to severe storms may occur today across parts of the northern/central Florida Peninsula, with gusty winds and hail the
main threats.

...Synopsis...
Mostly zonal flow with periodic low-amplitude shortwave troughs will
persist from the Gulf Coast states to Florida through the period. At
the surface, a stalled front will be present from the central Gulf
of Mexico to the central Florida Peninsula. This front will be a
focus for storm activity through the day Sunday with the potential
for a few strong to severe storms.

...Florida...
A mid-level shortwave trough located off the Florida Peninsula early
Sunday morning will shift eastward by morning and may provide enough
ascent for scattered storm activity across north-central Florida.
However, regional radar shows the surface front moving south from
Citrus to Flagler counties with areas north of this boundary more
stable. This may reduce the intensity of any convection which forms
across north-central Florida early in the day.

The aforementioned front is expected to stall somewhere near Orlando
with little movement expected through the day. Temperatures are
forecast to increase into the 80s with dewpoints ranging from the
upper 60s to low 70s by the afternoon. Nebulous forcing may keep
storm coverage isolated from late morning through mid-afternoon.
However, by the late afternoon/evening, weak mid-level height falls
are expected to overspread the region and this subtle ascent
combined with an unstable boundary layer should be sufficient for
scattered storm development. Effective shear in excess of 40 knots
should aid in storm organization and may support some supercell
structures. Mid-level lapse rates around 7 C/km are not overly
steep, but should be sufficient for a threat for isolated large
hail, especially if any sustained rotating updrafts can develop.
Overall, scattered strong storms with isolated severe storms are
expected with a threat for both large hail and damaging winds.

An isolated strong to severe storm threat may persist overnight as
the low-level jet strengthens and low-level moisture advection
sustains surface based instability ahead of the surface front as it
slowly moves south along the Peninsula.

Elsewhere, some gusty winds may accompany storm activity in the
northern Rockies as storms form in an environment with a dry
sub-cloud layer and moderately strong northwesterly flow 0.5 to 1 km
AGL. Limited instability precludes the addition of a marginal risk
at this time.

..Bentley/Jewell.. 04/18/2021

$$
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ACUS01 KWNS 221240
SWODY1
SPC AC 221238

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0738 AM CDT Sat May 22 2021

Valid 221300Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTRAL/SOUTHERN
HIGH PLAINS...

...SUMMARY...
Scattered severe hail and wind along with a few tornadoes are
possible across the central and southern High Plains this afternoon
through about dusk.

...Central and southern High Plains...
Within a meridional mid to upper-level flow regime downstream of an
amplified trough over the West, the western extent of mid 50s to low
60s surface dew points have reached the High Plains of eastern
CO/NM. While some eastward mixing will occur, multiple rounds of
scattered thunderstorms are expected to begin during the early
afternoon. Low-level hodographs initially may remain modest, but
should enlarge with time by late afternoon. A mixed mode of
supercells evolving into broader clusters is anticipated,
particularly in two regimes focused on eastern NM and separately in
northeast CO to western NE. Moderate buoyancy should develop within
confined corridors just ahead of this convection which should
support potential for a few tornadoes, in addition to severe hail
and wind.

...Central TX...
An MCV located just east of San Antonio should gradually advance
northwest across central TX through this afternoon. Low-topped
showers and isolated thunderstorms are expected to peak in coverage
from late morning through afternoon. A belt of enhanced 0-1 km shear
within the eastern quadrant of the MCV coupled with limited
boundary-layer heating may be sufficient for the threat of
brief/weak tornadoes.

...Northern MN...
Isolated thunderstorms may develop during the late afternoon to
early evening along the trailing portion of a modest warm conveyor
belt along/just ahead of a slow-moving cold front. The presence of
an upstream mid-level ridge over the Dakotas within a pronounced
gradient of mid-level westerlies suggest the corridor of severe
potential should remain spatially confined. Isolated severe hail and
locally damaging winds are possible.

..Grams/Mosier.. 05/22/2021

$$
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ACUS01 KWNS 231208
SWODY1
SPC AC 231207

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0707 AM CDT Sun May 23 2021

Valid 231300Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS WESTERN
SD/NE...

...SUMMARY...
Scattered to numerous severe thunderstorms are expected across a
large portion of the western Great Plains. The most likely corridor
for a few tornadoes and significant severe wind/hail is from western
South Dakota to the central High Plains.

...Western/central SD to the CO/KS border...
A surface cyclone in the lee of the Front Range will deepen as it
tracks north-northeast into western SD by this evening. Northward
advancement of the low in tandem with the surface warm front will
result in poleward advection of upper 50s to lower 60s surface dew
points towards the SD/ND border. Moderately steep mid-level lapse
rates of 7-7.5 C/km should support an increasingly expansive plume
of moderate buoyancy with MLCAPE of 1000-2000 J/kg by peak heating.

Pronounced mid-level height falls will overspread the region as a
vort max embedded within the basal portion of the broader trough
over AZ ejects northeast. Accompanied by an intense speed max,
thunderstorms will rapidly develop by early to mid-afternoon within
a strengthening deep-layer shear regime. Supercells will be favored
initially but a quick transition into a northeast-moving QLCS is
expected near the WY/SD/NE/CO border areas given the meridional flow
regime. Large hail will be likely mainly early, with severe wind
gusts becoming the primary hazard as upscale growth occurs across
western portions of SD/NE.

The potential for a few tornadoes is apparent across three primary
corridors within the ENH and SLGT risk regions. First, any storm in
proximity to the surface cyclone and warm front, where locally
enhanced 0-1 km SRH (at or above 200 m2/s2) will exist. Second,
embedded QLCS circulations are also possible as the line matures
during the late afternoon to early evening. Finally to the south of
the QLCS, a couple discrete supercells may persist through about
dusk near the CO/KS border amid plentiful low-level moisture/SRH.

...Southern High Plains...
Isolated to scattered thunderstorms are expected to develop during
the afternoon in the vicinity of the dryline from the Raton Mesa
vicinity to the Trans-Pecos of far west TX. A mix of supercells and
multicell structures will be most favored in the Raton Mesa vicinity
along the glancing periphery of the ejecting trough. Large hail,
severe wind gusts, and a tornado or two are possible.

...Northeast...
Convective coverage will likely remain sparse owing to modest
convergence along a predominately west/east-oriented cold front,
which will be pushing south across the region this afternoon.
Despite weak mid-level lapse rates, surface temperatures warming
into the 80s amid upper 50s to low 60s dew points should support
weak buoyancy with MLCAPE of 250-750 J/kg. Along the periphery of a
mid-level speed max ejecting across northern ME, adequate and nearly unidirectional deep-layer shear will exist for a few cells capable
of producing locally damaging winds.

..Grams/Mosier.. 05/23/2021

$$
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ACUS01 KWNS 191259
SWODY1
SPC AC 191257

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 AM CDT Sat Jun 19 2021

Valid 191300Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
CENTRAL PLAINS...LOWER MISSOURI/OHIO VALLEYS...MID-ATLANTIC...AND
CENTRAL GULF COAST...

...SUMMARY...
Damaging thunderstorm wind and isolated large hail are possible from
portions of the central High Plains to the Mid-Atlantic. A tornado
threat also exists over parts of the central Gulf Coast States to
southwestern Georgia, east of the inland track of Tropical Storm
Claudette.

...Synopsis...
In mid/upper levels, the main belt of northern-stream westerlies
will become more cyclonic through the period from the northern
Rockies to the Northeastern CONUS, as a series of shortwaves lead to
height falls. As this occurs, the strong and persistent anticyclone
to the south, over the Desert Southwest, will shift southward
slightly, with the 500-mb high approaching the southern border of AZ
by the end of the period. In between, a perturbation initially
apparent in moisture-channel imagery over UT will move eastward,
reaching southern WY and the CO Western Slope by 00Z. This trough
should move over parts of the central Plains overnight, potentially
with some convective vorticity reinforcement.

Farther east, a strong shortwave trough will move from its present
location over the western Lake Superior region and WI across the
rest of the upper Great Lakes, with some weakening expected by 00Z
as it reaches the Lake Erie vicinity. The trough should pivot
eastward from there to southern New England by 12Z tomorrow. A weak
mid/upper low will remain over east-central/southeast TX in the CLL
area, as the perturbation accompanying T.S. Claudette ejects
northeastward across MS/AL.

The 11Z surface analysis showed a cold front across portions of
southeastern ON and Lake Ontario, which should move eastward/
southeastward into parts of NY and New England today into tonight.
The wavy frontal zone extended through a low over southern WI,
southwestward across extreme southeastern NE to another low near the
southern part of the CO/KS line. Frontolysis is expected along the
High Plains portion of the boundary today, though easterly flow
components to its north and relatively maximized low-level moisture
will persist.

...Central Plains...
Widely scattered to scattered thunderstorms should develop this
afternoon over western parts of the outlook area, from the NE
Panhandle across parts of eastern CO. As this activity moves
roughly eastward through the late afternoon and early evening, it
will encounter greater moisture and intensify, offering the threat
for damaging gusts and large hail. The wind threat will
increase/maximize when upscale cold-pool aggregation and related
forced ascent can occur, while the foregoing boundary layer remains
deep and well-mixed, favoring downdraft acceleration. As such, the
potential for significant/65+ kt gusts is maintained over parts of
the High Plains.

As aforementioned height falls occur from this area northward, winds
aloft will become more difluent and strengthen slightly,
contributing to favorable deep shear. Meanwhile, large-scale ascent
and low-level mass response will increase with the approach of the
UT perturbation, leading to increased convergence north of the
remnant front, near a lee trough. Destabilization will occur aloft
with the DCVA and in the boundary layer from strong diurnal/diabatic
heating, leading to steep lapse rates, with peak MLCAPE in the
2000-2500 J/kg range. This will support the initial development and
upscale growth. Eastward extent of the nocturnal wind threat into
lower elevations and greater MLCINH (but also a strengthening
southerly LLJ) is uncertain, and largely dependent on depth/strength
of the MCS cold pool.

...Lower Missouri/Ohio Valleys...
Widely scattered to scattered thunderstorms in clusters are possible
this afternoon and evening, offering damaging gusts and severe hail.
Aggregated outflow from the prior day's and night's convection has
left a boundary across parts of northeastern KY and southern IN/IL,
to near STL, and west-northwestward across northern MO. Isolated
severe hail may be noted this morning with elevated convection north
of the boundary, though the supportive west-southwesterly to
westerly LLJ branch should weaken over the next few hours.

Despite weak shortwave ridging behind the upper Great Lakes trough,
strong low-level moisture/heating are likely along and south of the
boundary, which may drift back northward over parts of MO. A
boundary-parallel corridor of MLCAPE in the 3000-4000 J/kg range is
possible, amidst surface dew points from the upper 60s to low 70s F,
weak CINH, and a deep troposphere to aid in the development of
deeply buoyant profiles. Although forecast soundings suggest modest
deep shear, localized low-level shear/vorticity enhancement by the
boundary, and well-mixed subcloud layers on the warm side, may aid
storm organization as well. Low-level warm/moist advection may help
some of the convection to persist at severe levels tonight across
the Ohio Valley region. A relative minimum in severe potential may
exist between this regime and that over the central Plains; however,
confidence in that is not high enough yet to carve out lower
unconditional probabilities.

...Mid-Atlantic/Northeast...
Widely scattered to scattered thunderstorms are expected to form
through this afternoon over western parts of the outlook area,
especially over portions of western/central PA toward northern MD,
and move eastward with the threat for strong-severe gusts and large
hail. Some guidance indicates the potential for upscale clustering
over the lower DE Valley region and/or NJ before activity moves
offshore. Large-scale lift is expected to increase over the region
ahead of the upper Great Lakes shortwave trough, spreading ahead of
the cold front. Meanwhile, low-level destabilization will occur
diurnally, steepening deep-layer lapse rates with favorable moisture
in place. An area of 500-1500 J/kg MLCAPE should result, amidst
favorable deep shear. Although low-level flow will be weak and
veered, a 45-55-kt 500-mb speed max should shift over the region,
contributing to effective-shear magnitudes in the 35-45-kt range.
Organized multicells and isolated supercells are possible.

A separate area of thunderstorms should develop this afternoon
across portions of northeastern New England, along or ahead of the
cold front, offering isolated damaging gusts and marginally severe
hail. A zone of regionally maximized large-scale UVV -- preceding a
compact mid/upper cyclone and related shortwave trough now located
over western QC southeast of James Bay -- should spread over the
region atop a destabilizing boundary layer with diurnally minimized
MLCINH. A well-mixed boundary layer will support potential for
hail/gusts to reach the surface, beneath 500-1200 J/kg MLCAPE.
Effective-shear magnitudes around 30-40 kt will support some
storm-scale organization.

...Gulf Coast...
See tornado watch 284 and related mesoscale discussion for the
near-term tornado potential with what now is T.S. Claudette. This
highly asymmetric and strongly sheared cyclone is forecast by NHC to
turn northeastward, then east-northeastward across MS/AL through the
period. [See NHC advisories for latest specific track/intensity
forecasts and tropical watches/warnings.] The tornado potential
should remain displaced well away from the center, across those
portions of the outer eastern semicircle that can destabilize
sufficiently to support sustained supercells. That condition will
remain most probable relatively close to the coast, both in
persistent convergence/convective bands initially located over
southwestern AL and the FL Panhandle, southward over the Gulf.
Isolated discrete supercells also are possible east of the bands.

Theta-e advection and diurnal heating should destabilize the
boundary layer across the FL Panhandle, southeastern AL and perhaps southwestern GA as favorable low-level shear/hodographs spread
eastward through the outlook area. The tornado threat should
diminish this evening, both with inland/northeastward extent and
with time, as Claudette continues to gain distance from the Gulf,
flow veers to its south, and the most-favorable buoyancy and wind
profiles become more displaced from each other.

..Edwards/Broyles.. 06/19/2021

$$
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ACUS01 KWNS 200533
SWODY1
SPC AC 200532

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1232 AM CDT Sun Jun 20 2021

Valid 201200Z - 211200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN
IOWA TO SOUTHERN LOWER MICHIGAN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
ENHANCED RISK FROM THE MID MISSISSIPPI VALLEY INTO THE LOWER GREAT
LAKES ALONG WITH PARTS OF THE SOUTHEAST...

...SUMMARY...
Scattered severe storms are expected across the Midwest into the
lower Great Lakes/upper Ohio Valley. Large hail, severe/damaging
winds, and a few tornadoes are possible. Damaging winds and a couple
of tornadoes are also possible across the Southeast.

...Midwest to Lower Great Lakes...

Late Saturday central High Plains convection has spread downstream
and matured into a significant MCS as it tracks east along the NE/KS
border. Forward propagation appears to be reasonably similar to the
latest NAM with the leading edge of the MCS likely spreading across southwestern into south-central IA early in the period. One concern
is how poorly the models are handling the strong, sustained
convection across northern MO. This activity continues to propagate
northwest and will likely be absorbed into a larger complex by
daybreak. The disruptive potential of this interaction is unknown.
Even so, it appears a corridor of strong instability should evolve
from northern IL into southern lower MI. Approaching convectively
induced short-wave trough, strong heating, and the potential for a
low-level confluence zone to be draped across this region suggest
the potential for significant severe. Have opted to extend the ENH
Risk downstream across southern lower MI and adjacent portions of
northern IN/northwest OH as forecast soundings are impressively
buoyant and strongly sheared. Profiles favor supercells but the
early-day MCS will likely continue, in some form, through the day as
it spreads downstream. If supercells evolve, tornadoes and large
hail threat will increase with this activity. Otherwise, damaging
winds can be expected.

Later in the afternoon, surface heating should contribute to frontal
convection that will initiate across the upper MS Valley, then
spread/develop along the wind shift into eastern KS. Steep lapse
rates, strong surface-6km shear, and abundant instability suggest
the potential for very large hail with supercells in the wake of the
early-day MCS.

...Southeast...

Remnants of Claudette continue to shift downstream across AL into
GA/northern FL. Low-level shear will remain strong from northern FL
into coastal NC much of the period. While numerous showers/storms
will be ongoing at daybreak, latest NAM suggests a narrow corridor
of steeper surface-3km lapse rates within the zone of stronger shear
from northeast FL through coastal SC. This may increase the
potential for damaging winds and tornadoes. For these reasons have
increased severe probabilities across this region.

..Darrow/Lyons.. 06/20/2021

$$
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ACUS01 KWNS 201938
SWODY1
SPC AC 201937

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0237 PM CDT Sun Jun 20 2021

Valid 202000Z - 211200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
EXTREME EASTERN IOWA ACROSS CHICAGOLAND TO NORTHWEST OHIO AND
SOUTHERN LOWER MICHIGAN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
ENHANCED RISK...AND ALSO OVER PARTS OF GEORGIA AND THE CAROLINAS...

...SUMMARY...
Scattered severe storms are expected across the Midwest into the
lower Great Lakes/upper Ohio Valley. Large hail, severe/damaging
winds, and a few tornadoes are possible. Damaging winds and a couple
of tornadoes are also possible across the Southeast.

...20Z Update...

...Southeast Coast...
Air mass downstream of Tropical Depression Claudette continues to
destabilize amid modest heating and ample low-level moisture. As
mentioned in MCD #1034, a couple of transient supercells may pose an
isolated risk for a tornado or two through the afternoon. The
highest conditional risk for a tornado appears to be over parts of
eastern NC during the afternoon due to the larger hodographs.
Additionally, based on recent trends and the location of center of
TD Claudette, the severe risk across southeast GA has diminished
enough to remove Slight Risk-equivalent probabilities. Isolated
threat across southern GA/northern FL merits continued inclusion of
5% wind probabilities.

...Elsewhere...
Forecast delineated outlined in the previous outlook (discussion
below) remains valid and no changes are needed.

..Mosier.. 06/20/2021

.PREV DISCUSSION... /ISSUED 1122 AM CDT Sun Jun 20 2021/

...MO to OH...
Current water vapor loop shows a convectively augmented vort max
over northern MO. New thunderstorm development has occurred in the
past couple of hours in this region, with a corridor of rapid heating/destabilization occurring to the east from northeast MO into
northern IL. Storms will likely intensify through the afternoon
along this axis, with the risk of damaging winds, large hail, and
isolated tornadoes. 12z CAM solutions differ on the handling of
this cluster, but the potential appears to exist for a longer-lived
bowing structure that would track all the way into northern OH this
evening. Please refer to MCD #1032 for short-term details.

...MN/WI/IA/IL...
Latest surface analysis shows a low over west-central MN. clearing
skies ahead of the low, along with southerly low-level winds, will
help to warm/moisten and destabilize this area by mid-afternoon. A
consensus of model guidance shows intense thunderstorm development
later today over southeast MN, southwest WI, and parts of
northern/eastern IA. Large hail and damaging winds will be possible
with these storms. A combination of remnant cloud debris and
outflow boundaries complicate the scenario, but also increase the
conditional risk of supercells and perhaps a few tornadoes this
evening. If the storms over MO do not materialize into a
longer-lived bow, then this area of storms may persist for several
hours and track eastward across the ENH risk area.

...GA/SC/NC...
The remnants of Claudette continue to affect parts of GA and the
Carolinas today, with relatively strong low-level winds from
southeast GA into southern SC. Considerable daytime heating and
ample low level moisture will provide favorable thermodynamics for a
few intense afternoon thunderstorms capable of damaging wind gusts
and a few tornadoes.

...Southeast CO into southern KS late tonight...
A surface cold front will extend from eastern CO into southern KS
tonight, providing the focus for a few evening/overnight
thunderstorms. Sufficient CAPE/shear along this zone will pose a
risk of hail in the strongest storms.

$$
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ACUS01 KWNS 171253
SWODY1
SPC AC 171252

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0752 AM CDT Wed Apr 17 2024

Valid 171300Z - 181200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHERN LOWER MICHIGAN INTO THE OHIO VALLEY...

...SUMMARY...
Scattered thunderstorms capable of producing damaging winds, large
hail, and a few tornadoes should develop across parts of the Ohio
Valley and Lower Great Lakes this afternoon. Thunderstorms with
mainly a large hail threat may occur tonight over parts of the
central Plains.

...Synopsis...
An upper trough/low over the Upper Midwest this morning will
continue to move east-northeastward across the Great Lakes and OH
Valley today while gradually de-amplifying/weakening. An associated
40-60 kt mid-level jet will accompany this trough and overspread
much of the OH/TN Valleys. At the surface, a low over southeastern
MN/western WI should continue to gradually occlude through the day
in tandem with the weakening upper cyclone. An attendant cold front
will sweep eastward over the Lower Great Lakes/OH Valley through
this evening, while a warm front advances as far north as parts of
Lower MI and perhaps far western NY.

...Lower Michigan into the Ohio/Tennessee Valleys and
Mid-Atlantic...
Upper 50s to low 60s surface dewpoints are expected to be in place
ahead of the cold front late this morning/early afternoon. A
pronounced mid-level dry slot evident on water vapor satellite
imagery should aid in diurnal destabilization via a general lack of mid/upper-level cloud cover across parts of the OH Valley. As the
boundary layer gradually warms/moistens, around 1000-1500 J/kg of
MLCAPE should develop across southern Lower MI, eastern IN, and OH. Sufficiently strong low/mid-level winds will support 40-50 kt of
deep-layer shear and updraft organization. Current expectations are
for convection to develop along or just ahead of the cold front by
early afternoon, and subsequently spread quickly east-northeastward
across Lower MI, OH, and western PA through this evening. Tendency
may be for thunderstorms to quickly organize into a line, especially
across Lower MI which will be in closer proximity to the large-scale
ascent attendant to the upper trough/low. If this evolution occurs,
then severe/damaging winds would be the main threat with this
activity. Have expanded the Marginal and Slight Risks northward
across Lower MI to account for this potential.

Farther south across eastern IN and OH, forcing will gradually
become more limited, which may allow for somewhat lower thunderstorm
coverage initially. Even so, deep-layer shear will be strong enough
to support supercells, with large hail, damaging wind, and a few
tornadoes all possible. The best tornado potential may be focused
across parts of southeastern Lower MI and northern OH, in closer
proximity to the warm front and greater low-level shear. Some
upscale growth may also occur with this activity as it moves into
eastern OH and western PA, with a potentially greater threat for
damaging winds through the early evening before convection
eventually weakens.

Overall convective coverage should be lower across the TN Valley
into the Southeast, with weaker large-scale ascent present over
these regions. Still, isolated strong thunderstorms may occur this
afternoon and early evening in a weakly unstable but strong
deep-layer shear environment. Occasional hail and gusty winds appear
possible with the more robust cores. Based on latest guidance
trends, have trimmed the western extent of the Marginal Risk over
western KY/TN and northern MS.

Across the eastern Mid-Atlantic (northern VA/MD/DC/DE/south-central
PA), a well-mixed boundary layer and steep low-level lapse rates
forecast by some guidance may support occasional strong to damaging
winds with convection spreading eastward off the higher terrain of
the Appalachians and Blue Ridge Mountains. With limited instability,
the overall severe wind threat will likely remain isolated.

...Nebraska/Kansas into Iowa/Missouri...
An upper-level trough will move eastward across the north-central
CONUS tonight. A 40-45 kt southerly low-level jet will develop this
evening across parts of the southern/central Plains in response.
Thunderstorms should eventually initiate near the northern edge of
the low-level jet late this evening from central KS into far
southeast NE. Ample MUCAPE, steep mid-level lapse rates, and strong
shear in the cloud-bearing layer should support some threat for
large hail with this mainly elevated convection. The large hail
threat should to be greatest in the 04Z to 08Z time window with
initial development, but it may persist through the end of the
period. If convection can grow upscale into a small bowing cluster,
then isolated damaging winds may also occur.

A conditional threat for a supercell or two will exist farther south
across south-central/southeastern KS into far northeastern OK. Here,
modest low-level convergence along the intersection of a developing
warm front and dryline may be sufficient to initiate isolated
convection early this evening as the low-level jet strengthens. If
this occurs, then all severe hazards appear possible.

...Texas...
Very isolated thunderstorms may develop late this afternoon and
early evening across parts of south-central into central TX along a
surface dryline. If any convection can be sustained, it could
produce severe winds and hail. But, this threat currently appears
too conditional and uncertain to add low severe probabilities.

..Gleason/Bentley.. 04/17/2024

$$
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ACUS01 KWNS 191232
SWODY1
SPC AC 191231

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0731 AM CDT Fri Apr 19 2024

Valid 191300Z - 201200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON/EVENING FOR PARTS OF THE SOUTHEAST...

...SUMMARY...
Sporadic strong to marginally severe storms are possible over parts
of the Southeast later today.

...Southeast this afternoon/evening...
A closed midlevel low will evolve into an open wave as it moves
eastward over the Great Lakes and OH Valley. An associated surface
cold front will continue to move slowly southeastward from TX to the
southern Appalachians. A weak lead shortwave trough (enhanced some
by overnight convection) will move eastward over the southern
Appalachians and Piedmont this morning and the eastern Carolinas by
early-mid afternoon. Isolated thunderstorms will be possible with
the lead trough farther east in the Carolinas this afternoon, with
little larger-scale forcing for ascent farther west. Still, widely
scattered thunderstorm development will be possible this afternoon
in conjunction with weak ascent along the front and local terrain
circulations across the western parts of the MRGL risk area.
Weak-moderate buoyancy, modest deep-layer shear and steepening
low-level lapse rates will support some potential semi-organized
storms capable of producing isolated wind damage and marginally
severe hail for a few hours this afternoon/evening.

...TX through tonight...
Weak upslope flow along a slow moving cold front will favor
thunderstorm development over the east slopes of the Sierra Madre Oriental/Sierra del Burro this afternoon, with the potential for a
couple of supercells. However, it is not clear that storm motions
will bring the convection across the Rio Grande, and lingering
convective inhibition suggests storms will likely weaken if they
manage to cross the border. Later tonight in northwest TX, elevated
convection will likely develop atop the frontal surface, in a warm
advection regime downstream from a weak shortwave trough over AZ/NM.
Some small hail may occur given lingering steep midlevel lapse rates
and modest cloud-layer shear, but the potential for severe hail
appears too low to warrant an outlook area.

..Thompson/Kerr.. 04/19/2024

$$
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ACUS01 KWNS 201237
SWODY1
SPC AC 201235

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0735 AM CDT Sat Apr 20 2024

Valid 201300Z - 211200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
THROUGH LATE EVENING ACROSS CENTRAL/SOUTH TX...AND FROM SOUTHERN MS
TO SOUTHERN NC...

...SUMMARY...
Marginally severe storms capable of strong wind gusts and hail will
be possible mainly this afternoon/evening across portions of central
and south Texas, and from southern Mississippi to southern North
Carolina.

...TX into the Southeast this afternoon/evening...
South of a midlevel trough over the Great Lakes, a southern-stream
shortwave trough will progress eastward from southern AZ/NM toward
the lower MS Valley by Sunday morning. An associated surface
baroclinic zone from south TX into the Carolinas will move only
slowly southward through the period, providing a focus for isolated
to scattered thunderstorm development. The more widespread
convection is expected across TX near and to the north of the front,
based on proximity to the richest moisture and the southern-stream
trough.

Boundary-layer dewpoints in the 60s and surface heating in cloud
breaks will drive MLCAPE in the 1000-2000 J/kg range immediately
south of the front across the Southeast this afternoon. Vertical
shear will be relatively weak as a result of westerly wind profiles
with only modest speed increases from the low to midlevels. The
moderate buoyancy, weak vertical shear and steep low-level lapse
rates will favor isolated strong/damaging outflow gusts for a few
hours this afternoon/evening.

Richer low-level moisture (dewpoints in the lower 70s) and steeper
midlevel lapse rates will be present across south TX through this
evening. Initially elevated convection is expected to increase atop
the frontal surface from west central into central TX, and some of
this convection will approach the surface front this afternoon.
Separate surface-based thunderstorm development is also expected
along the front, and the storms will subsequently spread
east-southeastward into early tonight. Despite MLCAPE potentially
exceeding 2000 J/kg, the steeper lapse rates will be relatively high
in the profiles (above the 700 mb level), and vertical shear will
not be particularly strong. Though isolated large hail and wind
damage will be possible, along with some clustering of storms later
this afternoon into early tonight, a MRGL risk (5% hail/wind and 2%
tornado) appears to best characterize the overall severe threat in
TX.

..Thompson/Kerr.. 04/20/2024

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ACUS01 KWNS 211246
SWODY1
SPC AC 211245

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 AM CDT Sun Apr 21 2024

Valid 211300Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON/EVENING ACROSS NORTH FL/SOUTH GA...

...SUMMARY...
Isolated damaging winds near 60 mph and large hail near 1 inch
diameter will be possible for a few hours this afternoon/evening
across south Georgia and north Florida.

...North FL/south GA this afternoon/evening...
A low amplitude shortwave trough over the north central Gulf coast
will progress eastward over south GA/north FL by late afternoon, in
advance of an upstream trough over the mid MS Valley. An associated
cold front will move slowly southeastward and offshore of the
Carolinas this afternoon, and into central FL by Monday morning.
Regional 12z soundings from JAX/TLH show lingering steep midlevel
lapse rates and an associated cap which is expected to weaken from
the west by afternoon, when thunderstorm development will become
more probable with surface heating, ascent along the front, and with larger-scale ascent related to the approaching midlevel trough. The
warm sector ahead of the front across south GA/north FL will be
characterized by mid 60s dewpoints and surface temperatures ranging
from the mid 70s to lower 80s in cloud breaks by afternoon, where
MLCAPE could approach 1000 J/kg. Coincident with diurnal
destabilization, midlevel flow will increase to 50 kt with largely
straight hodographs and effective bulk shear of 35-40 kt. This
environment of moderate buoyancy and vertical shear will support the
potential for multicell clusters and/or low-end supercells capable
of producing isolated damaging gusts near 60 mph and large hail near
1 inch in diameter for a few hours this afternoon/evening.

..Thompson/Kerr.. 04/21/2024

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ACUS01 KWNS 221222
SWODY1
SPC AC 221220

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0720 AM CDT Mon Apr 22 2024

Valid 221300Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
ALONG THE SOUTHEAST FL COAST...

...SUMMARY...
Strong to locally severe thunderstorms, capable of marginally severe
wind gusts and hail, will be possible near the southeast Florida
coast this afternoon.

...Southeast FL coast this afternoon...
In conjunction with a midlevel shortwave trough moving over the
Southeast, a surface cold front will progress southward from central
to south FL through the day. Surface dewpoints near 70 F this
morning will likely decrease with surface heating/mixing, though
there is some uncertainty regarding the influence of morning
clouds/convection. Assuming a few cloud breaks by midday/early
afternoon, the more probable area for thunderstorm development this
afternoon will be near the southeast FL coast. This area will be
along the southern fringe of the stronger mid-upper westerlies,
where deep-layer shear/hodograph length will be sufficient for
semi-organized storms with a low-end wind/hail threat for a few
hours this afternoon.

...Elsewhere...
A midlevel trough will dig southeastward over the northern Plains
and upper Great Lakes by Tuesday morning, as an associated surface
cold front moves southeastward into the upper MS Valley and central
Plains. Isolated high-based thunderstorms may form late this
afternoon in the zone of deepest mixing along the front from
northeast CO into northwest KS, where gusty winds will be possible.
Elevated convection rooted near 700 mb is the more probable scenario
tonight atop the frontal surface from southern NE/northern KS into
southern IA/northern MO. Otherwise, weak/low-topped convection with
isolated lightning flashes will also be possible this
afternoon/evening within the midlevel cold pool over northern ND/MN.
Strong wind gusts will be possible given deep mixing and strong
synoptic flow over ND, but severe thunderstorms are unlikely.

..Thompson/Kerr.. 04/22/2024

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ACUS01 KWNS 231227
SWODY1
SPC AC 231226

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0726 AM CDT Tue Apr 23 2024

Valid 231300Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS
AFTERNOON/EVENING ACROSS NORTHWEST TX...

...SUMMARY...
Isolated severe thunderstorms capable of producing large hail (2+
inch diameter) and gusts to 65 mph will be possible this afternoon
and evening across northwest Texas. Additional strong storms
producing hail up to 1 inch diameter and gusts up to 60 mph are
possible from southeast Wisconsin and northern Illinois into Lower
Michigan.

...Northwest TX area this afternoon/evening...
No appreciable changes to the prior outlook. In the wake of a
midlevel trough crossing the Great Lakes, a surface cold front will
move southward across KS/OK today, eventually stalling by tonight
across southeast OK and northwest TX. There will be sufficient
cross-Rockies flow aloft for lee cyclogenesis across eastern NM and
adjacent west central TX, which will maintain southerly low-level
flow and northward advection of a modifying western Gulf air mass
into the frontal zone by mid-late afternoon. Strong surface heating
along the west edge of the returning moisture will result in a
sharpening dryline by late afternoon, with a dryline/front triple
point likely just off the Caprock. Isolated thunderstorm
development will be most probable near the triple point after 21z,
and convection will subsequently move southeastward before weakening
by late evening. The storm environment will be characterized by
moderate buoyancy (MLCAPE of 1500-2000 J/kg), steep midlevel lapse
rates near 9 C/km, and sufficient deep-layer shear for supercells.
Isolated very large hail of 2-2.5 inches in diameter will be the
main threat, along with a few 55-65 mph outflow gusts.

...Northern IL/southeast WI/Lower MI late this afternoon/evening...
Only minor changes to the MRGL risk area in lower MI. A midlevel
trough over the upper MS Valley this morning will continue
east-southeastward over the Great Lakes by Wednesday morning. An
associated surface trough will likewise move southeastward, and this
trough will be preceded by a band of rain with minimal buoyancy.
Behind the rain band, surface heating with steepening low-level
lapse rates and cooling midlevel temperatures will support weak
surface-based buoyancy just ahead of a secondary frontal surge.
Some low-topped convection will be possible in this zone late this
afternoon through late evening from northern IL/southeast WI into
lower MI. The storms could pose a marginal hail/wind threat.

..Thompson/Kerr.. 04/23/2024

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ACUS01 KWNS 241246
SWODY1
SPC AC 241245

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 AM CDT Wed Apr 24 2024

Valid 241300Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING
ACROSS WEST CENTRAL TX...

...SUMMARY...
Isolated large hail and damaging winds will be possible this evening
across west central Texas.

...West central TX this evening...
A midlevel shortwave trough off the southern CA coast will move
inland over southern AZ by the end of the period. Downstream,
shortwave ridging will persist over the Plains, though some increase
in westerly flow over the Rockies will contribute to lee troughing
across eastern CO/NM. The lee trough will maintain southerly
low-level flow and a gradual increase in low-level moisture to the
south of a warm front that will move slowly northward across OK and
the TX Panhandle. The moistening (boundary-layer dewpoints of 64-70
F and 100 mb mean mixing ratios of 12-14 g/kg) will occur beneath a
warm elevated mixed layer with midlevel lapse rates of 8-9 C/km,
which will drive large buoyancy (MLCAPE > 2000 J/kg) within a capped
warm sector.

The potential exception to this is along the developing dryline
across west central TX where surface heating/mixing could be deep
enough to remove convective inhibition, and isolated thunderstorm
development will be possible by this afternoon/evening. Confidence
in storm development is modest, but the environment with large
buoyancy, steep lapse rates and effective bulk shear greater than 40
kt will conditionally favor supercells capable of producing isolated
very large hail up to 2.5 inches in diameter and severe outflow
gusts of 60-70 mph. There will be an increase in low-level shear
this evening and low-level moisture will be greater compared to
yesterday, so an isolated tornado will also be possible in a narrow
time window this evening before inhibition increases and storms
weaken.

...OK into KS through tonight...
Elevated thunderstorms are ongoing over western OK in a zone of
low-midlevel warm advection and weak buoyancy likely rooted near 700
mb. Some of this convection could persist today while spreading
eastward, with a low-end hail threat. Additional elevated storms
are expected to form overnight from northeast OK into KS with
strengthening warm advection and increasing low-level moisture. A
couple of storms could produce isolated large hail the last few
hours of the forecast period.

..Thompson/Kerr.. 04/24/2024

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ACUS01 KWNS 241938
SWODY1
SPC AC 241937

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0237 PM CDT Wed Apr 24 2024

Valid 242000Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS
SOUTH PLAINS INTO THE PERMIAN BASIN...

...SUMMARY...
Isolated large hail and severe gusts will be possible this evening
from the Texas South Plains into the Permian Basin.

...20Z Update...

...TX South Plains into Permian Basin...
Forecast outlined in the previous discussion (appended below)
remains valid. Isolated thunderstorms still appear possible within
the destabilizing air mass from the TX South Plains into the Permian
Basin. Moderate buoyancy (i.e. MLCAPE from 2000 to 2500 J/kg) and
vertical shear (i.e. 0-6 km bulk shear from 40-50 kt) support the
potential for supercells within any sustained/mature convection.
Primary risk with any supercells would be large to very large hail
up to 2.5" in diameter and strong gusts up 70 mph. Tornado risk
still appears low, although non-zero given the increasing low-level
moisture and shear expected this evening.

...OK into Central/Eastern KS...
Thunderstorms are expected to develop tonight from central OK into
central and eastern KS as warm-air advection increases throughout
the warm sector. A few stronger storms capable of marginally severe
hail around 1" in diameter are possible through Thursday morning.

..Mosier.. 04/24/2024

.PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Apr 24 2024/

...West central TX this evening...
Water-vapor imagery this morning shows a midlevel low/shortwave
trough west of the southern CA/Baja California coasts and it will
move into the lower CO Valley by tomorrow morning. A mid-level
ridge situated over the southern Rockies will gradually move east
over the southern High Plains today. A lee trough will become more
pronounced throughout the day and act to maintain southerly
low-level flow across much of TX south of a warm front. The warm
front initially analyzed this morning near the Red River will slowly
move northward. Late morning surface observations over the Permian Basin/Concho Valley indicate low to mid 60s dewpoints. The 12z MAF
raob showed a 7.9 deg C/km 700-500 mb lapse rate, indicative of an
elevated mixed layer.

Weak forcing for ascent at best is expected beneath the mid-level
shortwave ridge, thereby limiting potential storm coverage. Despite
the associated forcing/capping concerns, convective inhibition will
erode considerably by 21-00z. Uncertainty remains regarding storm
development, but additional heating this afternoon --perhaps delayed
a bit due to considerable low cloud cover-- will result in moderate
buoyancy (2000-2500 J/kg MLCAPE). Relatively weak but veering winds
in the low levels beneath 65-kt westerly 250-mb flow will support a
conditional threat for supercells. Deeper mixing over the Permian
Basin may be enough to overcome and lead to a couple of storms by
late afternoon/early evening along the dryline. Isolated very large
hail up to 2.5 inches in diameter and severe outflow gusts of 60-70
mph are possible. There will be an increase in low-level shear this
evening and low-level moisture will be greater compared to
yesterday, so an isolated tornado will also be possible in a narrow
time window this evening before inhibition increases and storms
weaken.

...OK into KS through tonight...
Elevated thunderstorms near the OK/KS border late this morning are
likely the result of low-midlevel warm advection and weak buoyancy
rooted near 700 mb. Some of this convection could persist this
afternoon but it is uncertain whether intensification will occur
with this activity and whether a marginal hail threat develops. The
more probable risk for elevated storms will occur tonight coincident
with strengthening warm advection and increasing low-level moisture.

$$
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