770  
FXUS65 KBOU 071116  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
516 AM MDT MON SEP 7 2026  
   
KEY MESSAGES  
 
- BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH  
LOCALLY HEAVY RAIN IN A FEW AREAS ACROSS THE PLAINS.  
 
- TEMPERATURES WILL REMAIN VERY WARM, WITH ONLY SLIGHT COOL DOWN  
TUESDAY AND WEDNESDAY.  
 
- CHANCE OF AFTERNOON THUNDERSTORMS MAINLY PALMER DIVIDE AND EAST  
CENTRAL PLAINS ON TUESDAY,  
 
- WARMER AND DRIER FOR THURSDAY AND FRIDAY.  
 
- SOME POTENTIAL FOR A BRIEF COOLDOWN NEXT WEEKEND.  
 
 
   
DISCUSSION /THROUGH SUNDAY/  
 
ISSUED AT 233 AM MDT MON SEP 7 2026  
 
A UPPER LEVEL TROUGH WILL MOVE ACROSS THE NRN ROCKIES TODAY THRU  
TONIGHT WITH SW FLOW ALOFT ACROSS THE AREA. MONSOON MOISTURE WILL  
BE EMBEDDED IN THE FLOW WITH PW VALUES 150 TO 175 PERCENT ABOVE  
NORMAL. MLCAPE WILL BE AROUND 1000 J/KG FROM THE PALMER DIVIDE  
ACROSS THE FAR ERN PLAINS THIS AFTN WITH LOWER VALUES FURTHER  
WEST. OVERALL, WILL SEE A GOOD CHANCE OF SHOWERS/TSTMS THIS AFTN  
THRU THE EVENING HOURS, ESPECIALLY ACROSS THE PLAINS. THERE IS  
ENOUGH SHEAR FOR AN ISOLD SVR STORM OR TWO WHERE THE HIGHEST  
MLCAPE WILL EXIST THIS AFTN. IN ADDITION, WITH DECENT PW'S SOME  
LOCALLY HEAVY RAINFALL WILL BE POSSIBLE AS WELL. HIGHS THIS AFTN  
WILL BE IN THE UPPER 80'S TO MID 90'S ACROSS THE PLAINS.  
 
ON TUE, THE FLOW ALOFT WILL BECOME MORE WESTERLY AS A WEK COOL FRONT  
MOVES ACROSS THE PLAINS. THERE WILL STILL BE SOME MONSOON MOISTURE  
EMBEDDED IN THE FLOW, HOWEVER, PW VALUES WILL DECREASE, ESPECIALLY  
ACROSS THE NRN HALF OF THE AREA. BEST CHC FOR SHOWERS/TSTMS WILL BE  
OVER THE PALMER DIVIDE AND SERN AREAS OF THE PLAINS. MLCAPE IS FCST  
TO BE IN THE 500-800 J/KG RANGE, HOWEVER, SHEAR WILL BE BETTER SO  
CAN'T RULE OUT AN ISOLD SVR STORM OVER THE PALMER DIVIDE. HIGHS  
ACROSS THE PLAINS WILL BE IN THE 85 TO 90 DEGREE RANGE.  
 
FOR WED, THE FLOW ALOFT WILL BECOME MORE WNW AS A SURGE OF COOLER  
AIR MOVES ACROSS LATE TUE NIGHT INTO WED MORNING. THIS WILL LEAD  
MAINLY DRY CONDITIONS WITH HIGHS ACROSS NERN CO IN THE UPPER 70'S TO  
MID 80'S.  
 
LOOKING AHEAD TO THU AND FRI, THE FLOW ALOFT WILL BE MAINLY ZONAL  
WITH MINIMAL MOISTURE EMBEDDED IN THE FLOW. AS A RESULT, EXPECT  
MAINLY DRY CONDITIONS BOTH DAYS WITH WARMER TEMPERATURES AS READINGS  
OVER NERN CO RISE BACK INTO THE UPPER 80'S TO LOWER 90S.  
 
FOR NEXT WEEKEND, THE FLOW ALOFT WILL REMAIN ZONAL ON SAT AS ANOTHER  
WEAK FRONT MOVES ACROSS. AS A RESULT, HIGHS WILL DROP BACK INTO THE  
80'S ACROSS THE PLAINS. MEANWHILE, WILL LEAVE IN A SLIGHT CHC FOR  
AFTN TSTMS ACROSS THE AREA. ON SUN, THE FLOW ALOFT WILL BECOME MORE  
SW AS AN UPPER LEVEL TROUGH MOVES INTO THE NRN ROCKIES. THE GFS IS  
FASTER WITH MOVING A COLD FRONT ACROSS THE AREA DURING THE DAY WHILE  
THE ECMWF IS SLOWER. WITH SW FLOW ALOFT AND UPPER LEVEL TROUGH  
STILL TO THE NW OF THE AREA, ECMWF PROBABLY HAS A BETTER HANDLE ON  
TIMING OF FRONT. THUS MAY SEE HIGHS REACH THE UPPER 80'S TO LOWER  
90'S OVER NERN CO ON SUN BEFORE IT REACHES THE AREA SUN NIGHT.  
 
 
   
AVIATION /12Z TAFS THROUGH 12Z TUESDAY/  
 
ISSUED AT 512 AM MDT MON SEP 7 2026  
 
WINDS WILL BECOME LIGHT AND VARIABLE BY 14Z AND THEN TREND TO  
MORE EASTERLY AT BJC AND DIA BY 17Z. AT APA, WINDS WILL BE FROM  
THE SE BY 17Z AND THEN SWITCH TO THE NW BY 21Z. THERE WILL BE A  
CHC OF SHOWERS/TSTMS BY 22Z WHICH WILL LINGER THRU 02Z THIS EVENING.  
HAVE KEPT A PROB30 BETWEEN 22Z AND 02Z FOR -TSRA WITH BRIEF GUSTY  
WINDS UP TO 35 MPH POSSIBLE.  
 
BY 02Z, SHOWER/TSTM ACTIVITY SHOULD END WITH WINDS BECOMING SE/S  
AND THEN S/SSW BY 06Z.  
 
 
   
BOU WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION...RPK  
AVIATION...RPK  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab CO Page
Main Text Page