838  
ACUS01 KWNS 180043  
SWODY1  
SPC AC 180041  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0741 PM CDT THU SEP 17 2026  
 
VALID 180100Z - 181200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE CENTRAL HIGH PLAINS AND INTERMOUNTAIN WEST...  
   
..SUMMARY  
 
THUNDERSTORMS WITH ISOLATED SEVERE WIND GUSTS AND HAIL WILL BE  
POSSIBLE OVER PARTS OF THE INTERMOUNTAIN WEST EARLY THIS EVENING. A  
FEW STRONG TO SEVERE GUSTS MAY ALSO OCCUR ACROSS PARTS OF THE  
CENTRAL HIGH PLAINS.  
   
..INTERMOUNTAIN WEST  
 
AN UPPER-LEVEL LOW IS CURRENTLY LOCATED OVER NORTHERN CALIFORNIA,  
EVIDENT ON WATER VAPOR IMAGERY. MID-LEVEL FLOW IS SOUTHWESTERLY OVER  
MUCH OF THE INTERMOUNTAIN WEST WITH A DRY SLOT LOCATED FROM SOUTHERN  
NEVADA NORTHEASTWARD INTO NORTHERN UTAH AND SOUTHEAST IDAHO.  
SCATTERED THUNDERSTORMS HAVE DEVELOPED WITHIN THE NOSE OF THE DRY  
SLOT FROM NORTH-CENTRAL UTAH INTO EASTERN IDAHO. WITHIN THIS ZONE,  
THE RAP HAS A POCKET OF INSTABILITY WITH MLCAPE IN THE 1000 TO 1200  
J/KG RANGE. IN ADDITION, THE WSR-88D VWP NEAR POCATELLO, IDAHO HAS  
0-6 KM SHEAR NEAR 40 KNOTS. RAP FORECAST SOUNDINGS IN THE VICINITY  
HAVE LOW TO MID-LEVEL LAPSE RATES AROUND 8 C/KM. THIS ENVIRONMENT  
SHOULD SUPPORT A THREAT FOR HAIL AND ISOLATED SEVERE GUSTS FOR A  
COUPLE MORE HOURS THIS EVENING.  
   
..CENTRAL HIGH PLAINS  
 
ON WATER VAPOR IMAGERY, A MID-LEVEL SHORTWAVE TROUGH IS CURRENTLY  
LOCATED IN THE CENTRAL ROCKIES. THIS FEATURE WILL MOVE INTO THE  
CENTRAL HIGH PLAINS THIS EVENING. AT THE SURFACE, A WARM FRONT IS  
LOCATED FROM NORTHERN KANSAS INTO SOUTHWEST NEBRASKA. THE FRONT WILL  
MOVE NORTHWARD INTO WEST-CENTRAL NEBRASKA THIS EVENING. TO THE NORTH  
OF THE FRONT, A MOIST AXIS IS PRESENT WITH SURFACE DEWPOINTS FROM  
THE MID 60S TO THE LOWER 70S F. NEAR THE MOIST AXIS, THE RAP HAS  
MLCAPE IN THE 1500 TO 2000 J/KG RANGE. IN ADDITION, THE REGIONAL  
WSR-88D VWP NEAR NORTH PLATTE HAS 0-6 KM SHEAR AROUND 45 KNOTS,  
WHICH WILL SUPPORT AN ISOLATED WIND-DAMAGE THREAT FOR A FEW MORE  
HOURS THIS EVENING. LAPSE RATES ARE POOR WHICH WILL KEEP ANY SEVERE  
THREAT MARGINAL.  
 
..BROYLES.. 09/18/2026  
 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SPC Page
Main Text Page