LIVE MAP (ABOVE) ... SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1214 AM CDT Sat Sep 19 2026
Valid 191200Z - 201200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS...
...SUMMARY...
Thunderstorms with scattered severe wind gusts and large hail are
possible this afternoon and evening across parts of the central
Plains. Isolated severe wind gusts and hail may occur in parts of
the southern Plains and lower Missouri Valley. Isolated severe gusts
will also be possible from the Ohio Valley southward into the
Southeast.
...Central and Southern Plains/Lower Missouri Valley...
Mid-level heights will steadily fall over the central U.S. today, as
southwesterly flow aloft becomes established over much of the
region. At the surface, a cold front will advance southeastward
across the central Plains, and should be positioned from central
Kansas to far northwest Missouri by late afternoon. Ahead of the
front, surface dewpoints will be mostly from the mid 60s to mid 70s
F. As surface temperatures warm today, the moisture will contribute
to moderate destabilization. Thunderstorm initiation will become
likely by late afternoon across central and eastern Kansas, as
low-level convergence increases along and ahead of the front. A
complex of organized storms is expected to become established by
early evening and should persist for several hours.
RAP forecast soundings by early evening near the instability axis
have 0-6 km shear in the 30 to 40 knot range, with substantial
directional shear in the low-levels. In addition, low to mid-level
lapse rates are forecast to become steep. This environment should
support a large hail threat with supercells. A wind-damage threat
will also be possible, especially if a line segment can persist and
become organized during the evening. A marginal severe threat may
also develop southwestward across parts of the southern High Plains,
where hail and isolated severe gusts will be possible in the late
afternoon and early evening.
...Central High Plains...
An upper-level trough will move eastward across the Intermountain
West today, as flow aloft remains southwesterly over the central
Rockies and central High Plains. At the surface, a cold front will
advance southward across southeastern Colorado and western Kansas.
Behind the front, surface dewpoints in eastern Colorado will be in
the upper 50s to lower 60s F. The moisture will enable moderate
destabilization over much of eastern Colorado by afternoon. Warming
surface temperatures will lead to scattered thunderstorm development
in the higher terrain, with this convection moving eastward into the
central High Plains during the late afternoon. RAP forecast
soundings at 21Z in eastern Colorado have 0-6 shear in the 35 to 40
knot range, with 700-500 mb lapse rates near 8 C/km. This
environment will likely support a threat for large hail with
supercells. Isolated severe wind gusts will also be possible. A
marginal severe threat may also develop further north into parts of
eastern Wyoming and far western Nebraska, but instability will
remain relatively weak there.
...Ohio Valley/Southern Appalachians/Southeast...
West-northwesterly mid-level flow will be located over much of the
northeastern third of the U.S today. At the surface, an axis of
low-level moisture will be oriented from the Ohio Valley southward
into the southern Appalachians, along which moderate instability is
expected to be in place by afternoon. Convective development will be
possible in parts of the airmass, where localized surface heating
and low-level convergence become maximized. Thunderstorms in areas
with moderate instability could produce isolated severe wind gusts,
mainly during the late afternoon and early evening.
..Broyles/Thornton.. 09/19/2026
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TVYF9Q
Windy.com Temps | Gusts | WU KORD KPWK |
CLICK for this month's BIG night sky ... | RADAR FULL MAP SCREEN |
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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)
Saturday, September 19, 2026
SPC Sep 19, 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)




















