ACUS11 KWNS 211753
SWOMCD
SPC MCD 211753
MDZ000-DEZ000-VAZ000-DCZ000-WVZ000-211930-

Mesoscale Discussion 1691
NWS Storm Prediction Center Norman OK
1253 PM CDT Tue Jul 21 2026

Areas affected...portions of the Mid-Atlantic

Concerning...Severe potential...Watch likely

Valid 211753Z - 211930Z

Probability of Watch Issuance...80 percent

SUMMARY...Multiple rounds of numerous, strong to severe
thunderstorms will bring a risk for primarily damaging wind gusts to
portions of the Mid-Atlantic through this evening, with a couple of
brief tornadoes and isolated large hail also possible.

DISCUSSION...Scattered thunderstorms have developed along the Blue
Ridge as of 1750 UTC ahead of a mid-level shortwave trough that is
progressing eastward across the upper Ohio Valley. Expectation is
for this activity to spread eastward this afternoon with additional thunderstorms likely to progress into the region from the northwest
this evening. Filtered heating of the downstream environment has
resulted in temperatures warming into the upper 80s/near 90 F. With
dewpoints in the low/mid 70s, this is supporting moderately strong
buoyancy across the region. While effective shear of 35-45+ kts will
favor storm organization, widespread thunderstorm development and
cold pool consolidation are anticipated to yield a multicellular/outflow-dominant storm mode, with damaging to severe
wind gusts the primary risk. A couple of brief tornadoes and
isolated large hail will also be possible.

Additionally, guidance suggests that air mass recovery will occur in
the wake of these initial storms, which may allow the severe threat
to persist into this evening as additional convection progresses
southeastward into the region. Given this severe potential, watch
issuance will likely be needed in the next hour or two.

..Chalmers/Mosier.. 07/21/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!-YFpIjOY9imPmZia2mvxl9thDmhbkKXJgAdBoRDBO5cddXzEpESz0vJVzbRdgp7MFV5_xEVOnEiqNhi_e1sEDgF12U4$ for graphic product...

ATTN...WFO...PHI...AKQ...LWX...RNK...

LAT...LON 37348031 38057950 39047840 39467763 39467704 39397660
39147596 38857550 38557536 38147544 37417580 37067629
36927689 36917711 36747834 36737931 36818019 37078049
37218043 37348031

MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN


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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)