ACUS11 KWNS 042012
SWOMCD
SPC MCD 042012=20
MNZ000-IAZ000-SDZ000-042145-

Mesoscale Discussion 0980
NWS Storm Prediction Center Norman OK
0312 PM CDT Thu Jun 04 2026

Areas affected...eastern South Dakota into southwestern Minnesota

Concerning...Severe potential...Watch possible=20

Valid 042012Z - 042145Z

Probability of Watch Issuance...60 percent

SUMMARY...Thunderstorm coverage is expected to increase across
eastern South Dakota and southwestern Minnesota this
afternoon/evening, with potential for large hail and strong to
severe wind gusts.

DISCUSSION...Thunderstorm coverage has increased over the past hour
across portions of eastern South Dakota along/ahead of a slow moving
surface cold front currently extending southwestward from near the
ND/SD/MN border to south-central South Dakota. Ahead of this
boundary, latest objective analysis indicates lingering inhibition
is eroding, with warming temperatures contributing to MLCAPE of
1500-2000 J/kg. While a marginal increase in mid-level flow is
expected through the evening, effective shear will remain weaker
than areas farther west (generally remaining less than 30-35 kts).
This is likely to support an initially discrete storm mode (with
marginal supercell structures possible) with a gradual transition to
a more outflow-dominant, multicellular storm mode.

While mid-level lapse rates are not as steep compared to areas
farther west (evident via a comparison of the 18z UNR and ABR
observed soundings), large hail will be possible with initially
discrete convection and more robust updrafts. Steep low-level lapse
rates will also promote a risk for strong to severe wind gusts. A
brief tornado/landspout also cannot be ruled out should a stronger
low-level updraft interact with marginally enhanced surface vertical vorticity/low-level shear in close proximity to the surface front.
Trends are being monitored for possible Severe Thunderstorm Watch
issuance.

..Chalmers/Mosier.. 06/04/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!4MNUchgi9v-_H20aDVJmuUlDwJLaOw4a-tkxDCZUfij49pA1KdCcJl7WLBU9Pv__nFF-AunCr= kkkT9nqXlSfRrFvF2w$ for graphic product...

ATTN...WFO...MPX...FGF...FSD...ABR...

LAT...LON 43289941 44029936 44139934 44389861 44659813 45099763
45509739 45699705 45799668 45879633 45879600 45789562
45639553 45419544 44919541 44349567 43849607 43349652
43089737 43049813 43029869 43079917 43289941=20

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN


=3D =3D =3D
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