SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1110 AM CDT Mon Jul 27 2026

Valid 271630Z - 281200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MIDWEST...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE CENTRAL
HIGH PLAINS...

...SUMMARY...
Severe storms capable of strong to severe wind gusts and large hail
are expected across the Great Lakes and Midwest through tonight.
More sporadic occurrences of damaging wind are possible in the
Mid-Atlantic, Tennessee Valley, central High Plains, and southeast
Arizona.

...Midwest/Ohio Valley...
A large upper ridge remains present today over the central
Plains/Rockies, with moderately strong northwest flow aloft from the
Midwest into the OH Valley.  A very moist and unstable low-level air
mass resides from WI/IL into MI/IN/OH, where mostly clear skies will
result in hot afternoon temperatures and MLCAPE values over 3000
J/kg.  Multiple clusters of intense thunderstorms are ongoing over
parts of WI tracking southeastward. These storms will move through
this reservoir of high CAPE, leading to the potential for an active
severe weather event today.  However, details of how these clusters
evolve are uncertain.

Vertical shear across this region will support supercell structures,
capable of damaging winds, hail, and isolated tornadoes this
afternoon.  However, the greater concern is if storms can congeal
into a southeastward bowing system and that sweeps across Lower MI,
eastern IL, IN, and western OH.  Several morning CAM solutions
indicate that risk, with storms spreading into KY overnight before
weakening.  Unfortunately, this synoptic pattern does not lend
itself to a high-confidence convective forecast.

...High Plains...
Widespread clouds are affecting parts of western NE this morning. 
However, strong heating will occur north and south of these clouds,
leading to afternoon thunderstorms.  The most active area will
likely be over the Black Hills region where damaging winds and hail
are possible.  Farther south, widely scattered high-based
thunderstorms will affect eastern CO/western KS with a risk of
damaging wind gusts.

..Hart/Moore.. 07/27/2026

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