371  
ACUS11 KWNS 231958  
SWOMCD  
SPC MCD 231957  
COZ000-NEZ000-WYZ000-232200-  
 
MESOSCALE DISCUSSION 1278  
NWS STORM PREDICTION CENTER NORMAN OK  
0257 PM CDT TUE JUN 23 2026  
 
AREAS AFFECTED...NORTHERN COLORADO INTO SOUTHERN WYOMING  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 231957Z - 232200Z  
 
PROBABILITY OF WATCH ISSUANCE...60 PERCENT  
 
SUMMARY...THUNDERSTORM DEVELOPMENT APPEARS LIKELY IN THE COMING  
HOURS FROM NORTHERN COLORADO INTO SOUTHERN WYOMING. INITIALLY  
HIGH-BASED THUNDERSTORMS WILL INTENSIFY AS THEY SPREAD EAST INTO THE  
LOWER ELEVATION. WATCH ISSUANCE WILL LIKELY BE NEEDED AS THIS  
OCCURS.  
 
DISCUSSION...GRADUAL DEEPENING AND GLACIATION OF CUMULUS IS NOTED IN  
RECENT GOES DAY CLOUD PHASE IMAGERY WITHIN THE HIGHER TERRAIN OF  
NORTHERN CO AND SOUTHERN WY. THIS ACTIVITY IS LARGELY BEING DRIVEN  
BY A COMBINATION OF OROGRAPHIC ASCENT NEAR THE BASE OF A LAYER OF  
STEEP MID-LEVEL LAPSE RATES (OBSERVED BETWEEN 7.5 TO 8.0 C/KM BY  
UPSTREAM 18 UTC RAOBS). FURTHER DEEPENING AND THE ONSET OF LIGHTNING  
PRODUCTION IS EXPECTED WITHIN THE NEXT COUPLE OF HOURS AS DAYTIME  
HEATING CONTINUES. THE ZONAL FLOW REGIME ALOFT WILL ADVECT CELLS  
EASTWARD INTO THE ADJACENT HIGH PLAINS WHERE REGIONALLY RICH  
LOW-LEVEL MOISTURE (DEWPOINTS IN THE MID/UPPER 50S) IS IN PLACE AND  
IS SUPPORTING A PLUME OF 1000-2000 J/KG MLCAPE. CONVECTION EMANATING  
OFF THE HIGHER TERRAIN SHOULD BE ABLE TO INTENSIFY WITHIN THIS  
THERMODYNAMIC ENVIRONMENT AND MATURE INTO PRIMARILY DISCRETE  
SUPERCELLS GIVEN AROUND 45-50 KNOTS OF EFFECTIVE BULK SHEAR.  
RESIDUAL CAPPING AND FAIRLY WEAK FORCING FOR ASCENT AWAY FROM THE  
TERRAIN CASTS UNCERTAINTY ON OVERALL STORM COVERAGE, BUT STORMS THAT  
CAN BECOME SUSTAINED OVER THE HIGH PLAINS WILL LIKELY POSE A THREAT  
FOR VERY LARGE HAIL AS WELL AS SEVERE WIND GUSTS.  
 
..MOORE/GUYER.. 06/23/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...GLD...PUB...BOU...CYS...RIW...  
 
LAT...LON 38760482 40130559 40930615 41950705 42290701 42570649  
42500565 42030466 41490417 40860368 39920320 39210304  
38750306 38400331 38060395 37990434 38040475 38760482  
 
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH  
MOST PROBABLE PEAK WIND GUST...65-80 MPH  
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN  
 
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