163  
ACUS02 KWNS 281727  
SWODY2  
SPC AC 281725  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1225 PM CDT FRI AUG 28 2026  
 
VALID 291200Z - 301200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE  
NORTHERN GREAT BASIN AND NORTHERN PLAINS...  
   
..SUMMARY  
 
WIDELY SCATTERED STRONG TO SEVERE STORMS ARE EXPECTED ACROSS PARTS  
OF THE NORTHERN GREAT BASIN AND NORTHERN ROCKIES. SEVERE WIND GUSTS  
ARE THE MAIN THREAT. SCATTERED SEVERE STORMS ARE ALSO LIKELY ACROSS  
PORTIONS OF THE NORTHERN HIGH PLAINS, WITH POTENTIAL FOR LARGE HAIL  
AND DAMAGING WIND.  
   
..SYNOPSIS  
 
THE AXIS OF THE WESTERN US RIDGE WILL SHIFT EASTWARD CENTERING  
ACROSS THE MIDWEST D2/SATURDAY AS A MID-LEVEL LOW DIGS SOUTHWARD  
FROM THE PACIFIC NORTHWEST. STRENGTHENING SOUTHWESTERLY FLOW ALOFT  
WILL OVERSPREAD THE REGION FROM THE NORTHERN GREAT BASIN INTO THE  
NORTHERN ROCKIES/INTERMOUNTAIN WEST. WITH THE INCREASE IN MID-LEVEL  
FLOW ACROSS THE NORTHERN ROCKIES, LEE TROUGHING WILL INCREASE ACROSS  
THE CENTRAL/NORTHERN PLAINS, WITH A LEE CYCLONE DEVELOPING ACROSS  
THE WESTERN DAKOTAS.  
   
..NORTHERN GREAT BASIN INTO THE NORTHERN ROCKIES  
 
WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP WITHIN A  
BROAD REGION OF GREATER ASCENT ACROSS THE NORTHERN GREAT BASIN INTO  
THE NORTHERN ROCKIES. MOISTURE WILL BE PRIMARILY MID-LEVEL, WITH  
DEEPLY MIXED PROFILES, STEEP LOW TO MID-LEVEL LAPSE RATES, AND  
FAIRLY LARGE DEW POINT SPREADS NEAR THE SURFACE. THOUGH BOUNDARY  
LAYER MOISTURE WILL BE LIMITED, STEEP LAPSE RATES AND HEATING WILL  
SUPPORT AT LEAST MODERATE INSTABILITY BY THE AFTERNOON. WITH 40-50  
KT 500 MB FLOW ALOFT, SUFFICIENTLY STRONG DEEP LAYER SPEED SHEAR  
WILL PROMOTE A FEW ORGANIZED STORMS AND TRANSIENT SUPERCELLS CAPABLE  
OF DAMAGING WIND AND MARGINALLY SEVERE HAIL.  
   
..NORTHERN HIGH PLAINS  
 
UPSLOPE FLOW NEAR THE SURFACE LOW IN THE DAKOTAS SHOULD PROMOTE  
DEVELOPMENT OF THUNDERSTORMS NEAR THE BLACK HILLS AND ACROSS  
PORTIONS OF THE HIGH TERRAIN IN EASTERN WYOMING/SOUTHEASTERN  
MONTANA. STRENGTHENING SOUTHERLY FLOW WILL BRING MOISTURE NORTHWARD,  
WITH MODERATE TO STRONG INSTABILITY DEVELOPING BY THE AFTERNOON  
ACROSS THE WESTERN/CENTRAL DAKOTAS. ELONGATED AND LARGELY STRAIGHT  
HODOGRAPHS AND DEEP LAYER SHEAR AROUND 40 KTS WILL SUPPORT  
SUPERCELLS CAPABLE OF LARGE HAIL AND DAMAGING WIND.  
 
ACROSS EASTERN WYOMING, THERE IS LOW CONFIDENCE IN A MORE ORGANIZED  
CLUSTER EVOLVING THROUGH TIME AND MOVING INTO NORTHERN NEBRASKA.  
RECENT CAM GUIDANCE SUGGESTS A MORE FOCUSED CORRIDOR OF SEVERE WIND  
POTENTIAL. THE MARGINAL RISK WAS EXPANDED SOUTHWARD TO ACCOUNT FOR  
THIS POTENTIAL.  
 
..THORNTON.. 08/28/2026  
 
 
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