675  
FXUS65 KBOU 222039  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
239 PM MDT MON JUN 22 2026  
   
KEY MESSAGES
 
 
 
- STRONG TO SEVERE STORMS EXPECTED FOR THE PLAINS THIS AFTERNOON,  
PRODUCING LARGE/VERY LARGE HAIL, GUSTY WINDS, AND POSSIBLY A  
WEAK LANDSPOUT.  
 
- ADDITIONAL ROUNDS OF SEVERE STORMS EXPECTED TUE-WED, WITH  
INCREASING POTENTIAL FOR IMPACTS TO I-25 CORRIDOR AND LOCALIZED  
FLASH FLOODING. TEMPERATURES TO REMAIN SLIGHTLY BELOW NORMAL.  
 
- ELEVATED TO LOCALLY CRITICAL FIRE WEATHER CONDITIONS IN THE  
MOUNTAINS MOST AFTERNOONS, INCREASING IN SEVERITY THIS WEEKEND  
UNDER BUILDING HEAT AND STRENGTHENING WINDS.  
 
- DRIER AND CONSIDERABLY HOTTER FOR THE LOWER ELEVATIONS STARTING  
FRIDAY.  
 

 
   
DISCUSSION /THROUGH MONDAY/
 
 
ISSUED AT 230 PM MDT MON JUN 22 2026  
 
CURRENT OBSERVATIONS SHOW THUNDERSTORMS STARTING TO DEVELOP OVER THE  
EAST COLORADO PLAINS. THE DENVER CONVERGENCE-VORTICITY ZONE (DCVZ)  
IS CURRENTLY SITUATED JUST EAST OF THE DENVER METRO, WHICH IS  
PROVIDING AN AREA OF ENHANCED SURFACE VORTICITY. BULK SHEAR VALUES  
OVER EASTERN COLORADO ARE IN CURRENTLY IN THE 40-50KT RANGE,  
ALTHOUGH THE BETTER 0-3 KM STORM RELATIVE HELICITY (SRH) VALUES ARE  
LOCATED OVER OUR NORTHEASTERN CWA COUNTIES. NEVERTHELESS, THE  
AFOREMENTIONED PARAMETERS, COMBINED WITH PRECIPITABLE WATER (PW)  
VALUES AROUND 0.70"-1.00", AND STEEP LAPSE RATES (~8 C/KM), WILL  
SUPPORT THE DEVELOPMENT OF SUPERCELLS ABLE TO PRODUCE LARGE HAIL,  
GUSTY WINDS, AND WEAK LANDSPOUTS. LOCALIZED FLASH FLOODING WILL ALSO  
BE A CONCERN WITH ANY SLOW-MOVING STORMS THIS AFTERNOON, AS WELL  
AS OVER THE NEXT FEW DAYS, ESPECIALLY OVER AREAS WITH LEFTOVER  
SOIL MOISTURE FROM THE PREVIOUS DAY'S STORMS. WHILE THE PRIMARY  
THUNDERSTORM THREAT WILL LIKELY BE OUT OF THE AREA BY 7PM,  
ADDITIONAL ELEVATED THUNDERSTORMS CANNOT BE RULED OUT LATER IN THE  
EVENING, AS WE HAVE SEEN OCCUR OVER THE LAST FEW EVENINGS WHERE  
OUTFLOWS FROM FARTHER EAST HAVE TRIGGERED CONVECTIVE INITIATION.  
 
A COLD FRONTAL PASSAGE IS EXPECTED TO BRING NORTHERLY FLOW INTO THE  
REGION TUESDAY MORNING, AS WELL AS THE POTENTIAL FOR SOME PATCHY LOW  
CLOUDS. SEVERE THUNDERSTORMS WILL BE POSSIBLE AGAIN TOMORROW.  
HOWEVER, THE INITIAL CONVECTIVE ENVIRONMENT WILL FACE A FEW MORE  
CHALLENGES EARLIER IN THE DAY, GIVEN THE SLIGHTLY DRIER SURFACE  
DEWPOINTS BEHIND THE FRONT, AND NORTHERLY WINDS, AS OPPOSED TO THE  
MOISTER SOUTHEASTERLY FLOW THAT IS IN PLACE TODAY. HOWEVER, THE  
SHEAR PROFILE TOMORROW LOOKS TO BE MORE FAVORABLE FOR ROTATING  
UPDRAFTS, WITH HIGH-RES MODEL SOUNDINGS SHOWING CURVED HODOGRAPHS,  
AND A FEW ISOLATED BUT LONGER-LIVED SUPERCELLS. ALL HAZARDS WILL BE  
POSSIBLE WITH ANY STORMS THAT DEVELOP TOMORROW AFTERNOON AND  
EVENING, ALTHOUGH THE PRIMARY CONCERN IS VERY LARGE HAIL (>  
2.00").  
 
WEDNESDAY AND THURSDAY WILL BRING MORE ROUNDS OF SEVERE WEATHER  
POTENTIAL (MAINLY HAIL), DRIVEN BY ZONAL FLOW ALOFT AND LOW-LEVEL  
MOISTURE ADVECTION FROM THE SOUTHERN U.S. PLAINS. THE PW CONTENT IN  
PLACE OVER THE DENVER AREA THROUGH MOST OF THIS WEEK IS AT THE  
90TH PERCENTILE OF CLIMATOLOGY FOR LATE JULY, WHICH IS WHEN THE  
ANNUAL PEAK OF PW VALUES OCCURS. HOWEVER, THE HIGH TERRAIN TO THE  
WEST IS A DIFFERENT STORY, GIVEN THAT THIS SURGE IN MOISTURE WILL  
BE CONFINED TO THE LOW ELEVATIONS OF EASTERN COLORADO AND THE  
FOOTHILLS. AS SUCH, ELEVATED TO LOCALLY CRITICAL FIRE WEATHER  
CONDITIONS WILL PERSIST OVER THE MOUNTAINS AND HIGH VALLEYS WHERE  
RELATIVE HUMIDITIES WILL DROP INTO THE TEENS AND SINGLE DIGITS  
EACH AFTERNOON, WITH WINDS GUSTING TO 20-35 MPH.  
 
WIDESPREAD CRITICAL FIRE WEATHER CONDITIONS ARE STILL ON TRACK TO  
ARRIVE ON SATURDAY AS AN APPROACHING UPPER LEVEL TROUGH PUSHES  
THE MOIST AIRMASS IN PLACE EASTWARDS WHILE ALSO CAUSING WINDS TO  
INCREASE DUE TO THE TIGHTENING PRESSURE GRADIENT.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
 
 
ISSUED AT 1211 PM MDT MON JUN 22 2026  
 
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE FORECAST PERIOD. THE  
DENVER CYCLONE MOVED DIRECTLY OVER KDEN BETWEEN 15Z AND 17Z THIS  
MORNING. TDEN SHOWS THAT THE CYCLONE IS NOW LOCATED A FEW MILES TO  
THE EAST OF KDEN. AS A RESULT, WINDS HAVE NOW SHIFTED TO NNW  
ACROSS THE ENTIRE KDEN AIRPORT PROPERTY.  
 
TSRA DEVELOPMENT IS STILL ON TRACK FOR THIS AFTERNOON WITH KAPA  
HAVING THE HIGHEST CHANCE. ACARS SOUNDINGS SHOW A CAP STILL IN A  
PLACE, SO HAVE PUSHED TSRA CHANCES BACK TO START AT 19Z AT KAPA  
AND 20Z AT KBJC AND KDEN. ALL THREE TERMINALS HAVE THE CHANCE TO  
EXPERIENCE GUSTY OUTFLOW WINDS THIS AFTERNOON OF ABOUT 25 TO 30  
KTS FROM THUNDERSTORMS AS THEY MOVE TO THE EAST.  
 
BY THIS EVENING, WINDS WILL STAY ELEVATED WITH GUSTS AS HIGH AS 25  
KTS GIVEN THE CONTINUED OUTFLOW ENHANCED WINDS ESPECIALLY AT KDEN  
AND KAPA. AT KBJC, NNW WINDS SHOULD STAY AROUND 10 KTS FOR MOST  
OF THE NIGHT AFTER ABOUT 05Z. A FRONT WILL PUSH THROUGH FROM NORTH  
TO SOUTH FOR ALL THREE TERMINALS BETWEEN 13Z AND 15Z TOMORROW  
MORNING WITH GUSTY WINDS FROM THE NORTH. BY TOMORROW AFTERNOON,  
WINDS SHOULD SETTLE INTO A MORE NE DIRECTION. SHOWERS AND  
THUNDERSTORMS WILL LIKELY BE POSSIBLE ESPECIALLY AT KDEN AND KAPA  
TOMORROW AFTERNOON WITH THE THREAT FOR GUSTY OUTFLOW WINDS ONCE  
AGAIN, BUT THERE IS LOW CONFIDENCE IN EXACT PLACEMENT OF  
THUNDERSTORMS AT THIS TIME.  
 

 
   
BOU WATCHES/WARNINGS/ADVISORIES
 
 
RED FLAG WARNING FROM NOON TO 8 PM MDT TUESDAY FOR COZ212-213-  
217.  
 

 
 

 
 
DISCUSSION...AA  
AVIATION...MV  
 
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