LIVE MAP (ABOVE) ... SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1100 AM CDT Tue Sep 30 2025
Valid 301630Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are unlikely through tonight.
...Synopsis and Discussion...
Upper ridging will be maintained today across the Midwest and Great
Lakes, while upstream troughing advances inland over the western
states. Multiple embedded mid-level shortwave troughs will encourage
thunderstorm development through the period from parts of the Great
Basin into the northern/central Rockies and adjacent High Plains.
Thunderstorms may also occur across parts of coastal WA with
low-topped convection in close proximity to an upper low off the
coast of British Columbia. Other isolated thunderstorms appear
possible this afternoon over portions of the southern Appalachians
and FL Atlantic Coast. For all these areas, weak instability and/or
modest shear should preclude organized severe thunderstorms.
..Gleason/Thornton.. 09/30/2025
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TNNbHY
Windy.com Temps | Gusts | WU KORD KPWK |
CLICK for this month's BIG night sky ... | RADAR FULL MAP SCREEN |
|---|
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 30, 2025
SPC Sep 30, 2025 1630 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)




















