322 

ACUS01 KWNS 191954

SWODY1

SPC AC 191953



Day 1 Convective Outlook  

NWS Storm Prediction Center Norman OK

0253 PM CDT Tue May 19 2026



Valid 192000Z - 201200Z



...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER

OHIO VALLEY INTO THE LOWER GREAT LAKES...AND PARTS OF CENTRAL/SOUTH

TEXAS...



...SUMMARY...

Scattered severe thunderstorms will be possible today from the

southern Plains into the lower Mississippi Valley/Mid-South, Ohio

Valley, and lower Great Lakes. Damaging winds and hail will be the

primary threats. A greater threat for large to very large hail

should exist across parts of west-central Texas.



...20Z Update...

The primary change to the forecast was to increase wind

probabilities in parts of South Texas. Convection within the Rolling

Plains should continue to develop this afternoon along a slowly

moving cold front. Given the moisture surge ahead of this activity,

it seems plausible that cold pool development will be robust enough

to support continued development southward into the overnight.

Recent HRRR guidance and the ECMWF support this possibility.

Elsewhere, only minor changes where made based on current

observations.



..Wendt.. 05/19/2026



.PREV DISCUSSION... /ISSUED 1119 AM CDT Tue May 19 2026/



...OH Valley and Lower Great Lakes...

Deep southwesterly flow is present today from southern IL into much

of the OH Valley and NY.  Visible satellite imagery shows mostly

clear skies in the region, allowing strong destabilization and

steepening low-level lapse rates.  The result will be a rather large

zone of favorable environment for strong/damaging wind gusts this

afternoon with any organized convection.  Given the continued trend

in morning model guidance of scattered clusters of storms in this

corridor, the SLGT risk area has been maintained.



...South-central TX...

A warm/moist and unstable air mass will develop this afternoon

across parts of west-central TX.  Scattered thunderstorm development

is expected along a cold front sagging into the region. with weak

supercells structures possible.  These storms will track

southeastward through the late afternoon/evening with a large hail

threat.  Eventual upscale growth into bowing structures may extend

the severe risk overnight into south-central TX.



...East TX/LA/AR...

Widespread overnight convection continues to build southeastward

across southeast OK and western AR.  This activity will persist much

of the day and spread across much of AR/East TX/northern LA, in a

region of relatively weak vertical shear and poor lapse rates. 

Storms may occasionally pose a risk of gusty/damaging winds, but the

overall threat appears marginal.



$$