Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0159 PM CST Thu Feb 19 2026

Valid 192000Z - 201200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN
ILLINOIS AND SOUTHERN INDIANA...

...SUMMARY...
Severe thunderstorms including a few tornadoes, large hail and
damaging wind gusts are expected across parts of the Midwest and
lower Ohio Valley today.

...20Z Update...
No changes to the ongoing forecast appear to be needed at this time.
Dewpoints have had a tendency to mix into the upper 50s F this
afternoon in the lower Ohio Valley region. Convection has thus far
struggled to mature/intensify as a result. Areas of southern
Illinois into southwestern Indiana should be favored for more robust
storm initiation over the next few hours as the shortwave trough
moves in from the west. See the previous discussion for additional
details.

..Wendt.. 02/19/2026

.PREV DISCUSSION... /ISSUED 1022 AM CST Thu Feb 19 2026/

...Midwest/Ohio Valley...
Recent surface analysis places a low over eastern KS with a dryline
extending southwestward from this low through central OK and into
west TX. A warm front also extends eastward from this low across
central MO through central IL and central IN, separating the
moistening airmass south from the stable and cold airmass north.
Surface observations currently show mid 50s dewpoints through
southern IL and southern IN, with the 60s dewpoints farther south
into western KY. This surface low is forecast to progress
northeastward across central MO and into west-central IL today
before continuing northeastward into the southern Lake Michigan
vicinity by early tomorrow. Continued northward moisture advection
is anticipated as this low progresses, but this low-level moistening
will be countered somewhat by boundary-layer mixing, resulting in
some uncertainty to how high the dewpoints will reach across the OH
Valley this afternoon. General consensus places upper 50s dewpoints
into the I-70 corridor by the late afternoon. 

These increasing dewpoints coupled with cold temperatures aloft and
afternoon temperatures in the upper 60s/low 70s should result in
modest airmass destabilization within the warm sector, despite a
relatively warm layer between 850-700 mb. In addition to improving
thermodynamics, the deep-layer southwesterly flow is forecast to
strengthen as well. The strongest mid-level flow will likely be
displaced just south of the better thermodynamics, but forecast
shear profiles are still quite robust across the OH Valley. The
general expectation is for this robust vertical shear (i.e.
effective bulk shear over 50 kt this afternoon) to somewhat
compensate for the more modest buoyancy, resulting in an organized
storm mode and supercells. 

The dryline will likely remain west of this region during the
afternoon, with the lift over the warm sector provided by a subtle
lead shortwave currently moving through southern MO. This shortwave
should interact with the warm sector across the OH Valley this
afternoon, supporting thunderstorm development. Overall coverage is
not expected to be high, but any storms that do mature could produce
all severe hazards, including tornadoes. Additionally, the robust
shear suggests that once a storm matures, it could persist for
several hours. Given this updraft persistence in the presence of
veering low-level wind profiles, a strong (EF2+) tornado is
possible.

Additional thunderstorms are possible along the front during the
evening and overnight from the TN Valley eastward into the central
Appalachians. A few strong to severe storms are possible, but
limited buoyancy should keep this potential isolated. Greatest
probability for a severe storm along the front currently appears to
be across western/middle TN and southern-central KY this evening.