725
ACUS02 KWNS 040558
SWODY2
SPC AC 040557

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Fri Jul 04 2025

Valid 051200Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE NORTHERN HIGH PLAINS...

...SUMMARY...
Strong to severe storms are likely across portions of the northern
High Plains tomorrow (Saturday), with hail and wind being the main
concerns. Isolated damaging gusts may also accompany the stronger
storms over the Upper Midwest.

...Synopsis...
Generally zonal mid-level flow will overspread the northern CONUS as
an upper trough impinges on the West Coast tomorrow (Saturday). A
pair of mid-level impulses will traverse the zonal flow, with one
impulse passing over the Great Lakes as the other impulse ejects
into the Northern High Plains. Over both locations, adequate
moisture and instability will be in place to support strong
thunderstorms. The best chance for severe thunderstorms will be over
the northern High Plains, where stronger vertical wind shear will
encourage storm organization.

...Northern into the central High Plains...
A belt of strong westerly 500 mb flow will overspread MT into the
northern High Plains Saturday afternoon with the passage of the
aforementioned mid-level impulse. A surface low will develop
somewhere across northern WY into southern MT, promoting moist
southeasterly low-level flow beneath the stronger mid-level
westerlies, resulting in over 50 kts of effective bulk shear.
Adequate low-level moisture, overspread by 8+ C/km low to mid-level
lapse rates, will boost MLCAPE to over 2000 J/kg in spots. The
moderate instability and strong deep-layer shear will promote
supercells and bowing segments capable of producing some severe wind
and hail. A tornado is also possible with the longer-lived, dominant
supercells.

Farther south into the central High Plains, deep-layer ascent and
shear should be considerably weaker, resulting in a lower coverage
of relatively less organized multicellular clusters. Storms here
should be high-based, overspreading a dry boundary layer deepening
into the 700-500 mb range by afternoon peak heating. Isolated severe
gusts are possible with the stronger multicellular clusters, and an
instance or two of severe hail cannot be ruled out.

...Great Lakes into the central Plains...
A weak surface cold front, associated with a surface low over the
Great Lakes, will progress southeastward across the western Great
Lakes into the central Plains as the eastern mid-level impulse
glances by to the north. Flow closer to the surface and aloft, and
thus vertical wind shear, will not be overly strong ahead of the
front. However, rich low-level moisture amid afternoon surface
heating will promote 2000-3000 J/kg MLCAPE and minimal convective
inhibition. Scattered multicells should develop along/ahead of the
front through the afternoon, the stronger storms of which may
produce wet downbursts and accompanying isolated damaging gusts.

..Squitieri.. 07/04/2025

$$