932 

ACUS01 KWNS 220602

SWODY1

SPC AC 220601



Day 1 Convective Outlook  

NWS Storm Prediction Center Norman OK

0101 AM CDT Sat Aug 22 2026



Valid 221200Z - 231200Z



...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF

THE UPPER OHIO VALLEY...



...SUMMARY...

Scattered damaging gusts are likely across the Ohio Valley with more

isolated damaging wind potential extending westward into the Mid

Mississippi Valley and southern Plains this afternoon/evening.

Isolated hail and damaging winds are also possible over the Front

Range, Great Basin and parts of the northern Rockies.



...OH and TN Valleys...

An upper low initially over the western Great Lakes is forecast to

deepen as it moves southeastward today and tonight. A belt of

stronger mid-level flow behind the trough will move into parts of

the Plains and Midwest. A weak surface low and trailing cold front

will move southeastward across the Lakes and into the upper OH

Valley through the day. Ahead of the front, upper 60s to 70s F

surface dewpoints and filtered diurnal heating should allow for

moderate destabilization, sufficient for scattered to numerous

thunderstorms by early afternoon. Despite generally modest to weak

deep-layer shear, steepening of lower/mid-level lapse will support

stronger downdrafts within organized multicell clusters. With time,

some upscale growth into linear segments is also possible and would

also favor a risk for scattered damaging gusts. This appears most

likely across central/eastern OH and KY into western PA/WV.



Farther south, more isolated storm coverage is expected ahead of the

front from the western Carolina Piedmont to the TN Valley. Steep

low-level lapse rates and enhanced low and mid-level northwesterly

flow will still support some risk for isolated damaging gusts.



...Ozarks/Mid MS Valley...

A weak convectively augmented shortwave trough is forecast to move

from southeastern KS and southern MO into northern AR along western

portions of a weak surface front by midday. Ahead of these features,

a very warm and humid air mass will be in place, which should allow

substantial diurnal destabilization and eventual thunderstorm

development. Enhanced northwesterly flow may help organize a few

thunderstorm clusters as they spread eastward from the Ozarks into

the ArkLaTex and mid MS Valley. Damaging wind gusts and some hail

are possible.



...Front Range and adjacent High Plains...

Post-frontal upslope flow, aided by a weak short wave impulse on the

eastern periphery of the upper ridge will support thunderstorm

development along/east of the Laramie mountains through Colorado

Front Range this afternoon. On the fringes of the stronger northwest

flow aloft, deep-layer shear will be marginal for storm

organization. Steep mid-level lapse rates and moderate buoyancy

could support some hail with the stronger updrafts. Isolated

damaging gusts are also possible, especially with any more

persistent thunderstorm clusters.



...Southern Plains...

Very hot surface temperatures (100+ F) are likely across parts of

western North TX into southwestern and central OK this afternoon.

Low-level convergence near a thermally enhanced surface low and weak

front will aid high-based thunderstorm development late afternoon

into the early evening. Weak buoyancy atop the steep low-level lapse

rates and deep mixed layer will favor very strong downdrafts within

the high-based storms. Isolated severe gusts (possibly 65-75 mph

gusts) associated with microbursts are possible as convection is

forecast to move southward through the evening.



...Northern Rockies to the Great Basin....

An upper low along the western periphery of the substantial

mid-level ridge over the Southwest will migrate northward toward the

international border as a belt of stronger mid-level flow

overspreads a plume of monsoon moisture from the Great Basin to the

Northern Rockies. Ascent from the upper wave and heating of the

modestly moist air mass should allow for weak destabilization and

scattered thunderstorm development. Steep lapse rates could support

isolated severe gusts.



Isolated hail is also possible with scattered thunderstorms from

eastern WA into the ID panhandle. Closer to the upper trough and

beneath strong mid-level flow, elongated hodographs may promote

organization with transient supercell structures. Cooler mid-level

temperatures could favor hail production despite modest overall

moisture.



..Lyons/Weinman.. 08/22/2026



$$