839  
ACUS03 KWNS 201931  
SWODY3  
SPC AC 201930  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0230 PM CDT MON APR 20 2026  
 
VALID 221200Z - 231200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE  
HIGH PLAINS...  
   
..SUMMARY
 
 
SEVERE THUNDERSTORMS CAPABLE OF HAIL AND GUSTY WINDS MAY DEVELOP  
DURING THE LATE AFTERNOON AND EVENING ACROSS PORTIONS OF THE HIGH  
PLAINS.  
   
..SYNOPSIS
 
 
A BROAD TROUGH WILL BEGIN TO MOVE INTO THE ROCKIES AND ADJACENT HIGH  
PLAINS. A SHORTWAVE TROUGH WILL EJECT INTO THE NORTHERN PLAINS IN  
ASSOCIATION WITH THE BROADER TROUGH. AT THE SURFACE, A DEEP SURFACE  
LOW WILL DEVELOP IN EASTERN MONTANA WITH A LEE TROUGH/DRYLINE  
EXTENDING INTO THE SOUTHERN HIGH PLAINS.  
   
..HIGH PLAINS
 
 
AS THE UPPER-TROUGH APPROACHES THE ROCKIES, THE LEE TROUGH AND  
DRYLINE ARE EXPECTED TO SHARPEN. FORCING FOR ASCENT WILL BE  
STRONGEST IN THE NEBRASKA PANHANDLE/WESTERN SOUTH DAKOTA VICINITY.  
THIS AREA IS ALSO HAS THE LARGEST VARIABILITY IN TERMS OF MOISTURE  
RETURN (THE NAM BEING MUCH MORE BULLISH THAN THE ECMWF). FARTHER  
SOUTH, MOISTURE WILL GENERALLY BE GREATER. GUIDANCE IS IN AGREEMENT  
THAT 60S F DEWPOINTS ARE PROBABLE IN THE TEXAS SOUTH PLAINS AND  
PERHAPS PARTS OF THE PANHANDLE. THE ISSUE FARTHER SOUTH WILL BE THE  
LACK OF SYNOPTIC ASCENT. TEMPERATURES BEHIND THE DRYLINE WILL BE IN  
THE UPPER 80S F TO PERHAPS LOW 90S F. THE DEPTH OF THE CIRCULATION  
MAY BE ENOUGH TO INITIATE AN ISOLATED STORM OR TWO, BUT CONFIDENCE  
IS STILL NOT OVERLY HIGH. ENVIRONMENTALLY, DEEP-LAYER SHEAR WILL BE  
ORIENTED ROUGHLY PERPENDICULAR TO THE DRYLINE, ESPECIALLY FROM  
WESTERN KANSAS SOUTHWARD. SUPERCELLS WOULD BE FAVORED IF STORMS  
DEVELOP. MLCAPE OF 1000 J/KG IN SOUTH DAKOTA TO 1500-2500 J/KG  
FARTHER SOUTH IS EXPECTED BY THE AFTERNOON. LARGE HAIL AND SEVERE  
WIND GUSTS WOULD BE POSSIBLE.  
   
..CENTRAL/EASTER MONTANA
 
 
WITH THE SURFACE LOW DEEPENING THROUGH THE DAY, AT LEAST MODEST  
MOISTURE RETURN NORTHWESTWARD IS ANTICIPATED INTO CENTRAL/EASTERN  
MONTANA. HOWEVER, MOISTURE WILL STILL BE QUITE SCANT ACROSS THE  
REGION. DEWPOINTS MAY NOT REACH THE 40S F. GIVEN THE FORCING FOR  
ASCENT, HIGH-BASED CONVECTION IS POSSIBLE. THE VERY DRY SUB-CLOUD  
LAYERS COULD LEAD TO GUSTY OUTFLOW WINDS. AT PRESENT, CONFIDENCE IN  
SEVERE GUSTS IS TOO LOW TO WARRANT WIND PROBABILITIES.  
 
..WENDT.. 04/20/2026  
 

 
 
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