LIVE MAP (ABOVE) ... SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1250 AM CDT Tue Sep 22 2026
Valid 221200Z - 231200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHEAST...AND IN THE VICINITY OF NORTH-CENTRAL AND
NORTHEASTERN UTAH....
...SUMMARY...
Thunderstorms with isolated severe wind gusts are possible today
across parts of the Southeast, and in the vicinity of north-central
and northeastern Utah.
...Southeast...
At the surface, a cold front will advance southward into the
Southeast today. The position of the front by afternoon will be from
the northern Gulf Coast States into southern Appalachians. Warming
surface temperatures and increasing low-level convergence near and
ahead of the boundary will result in scattered thunderstorm
development this afternoon. Surface dewpoints across the moist
airmass will mostly range from the mid 60s to mid 70s F. This will
aid destabilization, with MLCAPE expected to peak in the 1500 to
2500 J/kg in most areas ahead of the front. Although deep-layer
shear will be limited, the thermodynamic environment will be able to
support isolated severe wind gusts with convection that develops
within the strongest localized instability.
...North-central and Northeastern Utah/Far Southwest Wyoming...
A mid-level trough and low pressure center will move northeastward
across the Intermountain West today. Ahead of the system, a surface
low will deepen across western Utah. To the east and northeast of
the low, surface dewpoints will range from the mid 40s to mid 50s F.
This will be enough for the development of weak instability by
afternoon. MLCAPE is forecast to increase to around 1000 J/kg over
much of north-central and northeast Utah, as a cold pocket
associated with the approaching upper-level low begins to affect the
area. The Salt Lake City RAP forecast sounding at 21Z has 0-6 km
shear near 40 knots with steep low to mid-level lapse rates in the 7
to 8 C/km range. This should support an isolated potential for
supercells. Hail and isolated severe gusts would be the primary
threats.
..Broyles/Thornton.. 09/22/2026
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TVb9J3
Windy.com Temps | Gusts | WU KORD KPWK |
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MOBILE DEVICE? Turn sideways. Weather conditions directly above are near Lakefront. Top tabs refer to O'Hare (official).
Archives for the SPC Convective Outlook are updated daily (approximately) with a live map at the beginning of each article. Follow the link at the end of the article to check for current updates on the NOAA/NWS Storm Prediction Center website. Also, see Archives for Chicago's hourly weather data on CARDINAL NEWS Magazine.
CONVECTIVE | TORNADO | WIND | HAIL
O'Hare International Airport KORD
(Arlington Heights South)
Chicago Executive Airport KPWK
(Arlington Heights North)
Tuesday, September 22, 2026
SPC Sep 22, 2026 0600 UTC Day 1 Convective Outlook
SUNRISE AND SUNSET TIMES IN UTC (if you're not logged in to Google)
CHICAGO UTC-6 during CST (Central Standard Time, e.g., winter)
CHICAGO UTC-5 during CDT (Daylight Savings Time, e.g., summer)
CHICAGO UTC-6 during CST (Central Standard Time, e.g., winter)
CHICAGO UTC-5 during CDT (Daylight Savings Time, e.g., summer)




















