927  
ACUS01 KWNS 130609  
SWODY1  
SPC AC 130608  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0108 AM CDT WED MAY 13 2026  
 
VALID 131200Z - 141200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHERN UTAH  
NORTHWARD ACROSS EASTERN IDAHO...WESTERN WYOMING...AND PORTIONS OF  
WESTERN MONTANA...  
   
..SUMMARY  
 
SCATTERED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PORTIONS OF THE  
NORTHERN HIGH PLAINS WEDNESDAY AFTERNOON AND EVENING. SEVERE WIND  
GUSTS ARE THE PRIMARY HAZARD.  
   
.. SYNOPSIS  
 
AN AMPLIFIED, YET PROGRESSIVE, MIDLEVEL PATTERN WILL EXIST ACROSS  
THE US ON WEDNESDAY. A VIGOROUS SHORTWAVE TROUGH WILL MOVE EAST  
ACROSS THE NORTHERN ROCKIES AS A MEXICO-TO-CANADA MIDLEVEL RIDGE  
MOVES INTO THE CENTRAL US. DOWNSTREAM FROM THE RIDGE, AN AMPLIFIED  
TROUGH WILL DEEPEN FURTHER, DEVELOPING INTO A CLOSED LOW OVER THE  
NORTHERN MID-ATLANTIC AND SOUTHERN NEW ENGLAND REGION.  
 
... PORTIONS OF THE GREAT BASIN AND THE CENTRAL AND NORTHERN ROCKIES  
...  
 
AS THE POTENT MIDLEVEL SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN  
ROCKIES AN ATTENDANT 80-90 KNOT MIDLEVEL JET STREAK WILL OVERSPREAD  
NORTHERN PORTIONS OF THE AREA DURING THE AFTERNOON AND EVENING  
HOURS. AT THE SAME TIME, A COLD FRONT WILL PUSH EAST ACROSS THE  
REGION LEADING TO SCATTERED CONVECTION BY MID-TO-LATE AFTERNOON.  
FORECAST SOUNDINGS CONTINUE TO EXHIBIT INVERTED-V THERMODYNAMIC  
PROFILES AND INCREASING CLOUD-LAYER SHEAR. THE RESULT WILL BE FAST  
MOVING STORMS CAPABLE OF TRANSPORTING MOMENTUM DOWNWARD TO THE  
SURFACE. ADDITIONALLY, THE DRY SUB-CLOUD LAYER WILL SUPPORT THE  
POTENTIAL FOR SOME DRY MICROBURST POTENTIAL.  
 
   
.. OHIO VALLEY AND CENTRAL APPALACHIANS  
 
A SURFACE LOW WILL MOVE EAST FROM LOWER MICHIGAN TOWARD NORTHERN NEW  
YORK, DRAGGING A COLD FRONT EASTWARD ACROSS THE OHIO VALLEY AND  
CENTRAL APPALACHIANS BEFORE ENDING UP NEAR THE ATLANTIC COAST.  
TOWARD THE END OF THE FORECAST PERIOD, THE NORTHERN NEW YORK SURFACE  
LOW WILL REDEVELOP FARTHER SOUTHEAST ALONG THE FRONT NEAR THE  
ATLANTIC COAST.  
 
AHEAD OF THE FRONT, SURFACE DEWPOINTS SHOULD RISE INTO  
LOW-TO-MID-50FS CONTRIBUTING TO WEAK INSTABILITY WITH DIURNAL  
HEATING. THUNDERSTORMS SHOULD DEVELOP ACROSS THE AREA DURING THE  
AFTERNOON ALONG THE FRONT, WITH ADDITIONAL THUNDERSTORMS POSSIBLE  
ACROSS TERRAIN FAVORED AREAS ACROSS THE CENTRAL APPALACHIANS.  
SUFFICIENT VERTICAL SHEAR BENEATH A 50 KNOT MIDLEVEL JET AND MODEST  
LOW-LEVEL LAPSE RATES WOULD SUPPORT A MARGINAL WIND THREAT.  
 
   
.. TEXAS PANHANDLE INTO THE HIGH PLAINS OF SOUTHERN COLORADO  
 
STRONG DIURNAL HEATING BENEATH THE MIDLEVEL RIDGE MAY BE SUFFICIENT  
FOR CONVECTIVE INHIBITION TO ERODE AND ISOLATED THUNDERSTORMS TO  
DEVELOP ACROSS TERRAIN FAVORED AREAS. VERY STEEP LAPSE RATES WILL  
SUPPORT A HAIL AND WIND THREAT.  
 
..MARSH/WEINMAN.. 05/13/2026  
 
 
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