991  
FXUS65 KBOU 071806  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
1206 PM MDT MON SEP 7 2026  
   
KEY MESSAGES
 
 
- SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING,  
A FEW COULD BE STRONG TO SEVERE OVER THE PLAINS.  
 
- SLIGHTLY COOLER TUESDAY INTO WEDNESDAY WITH PRECIPITATION  
CHANCES SHIFTING MAINLY TO AREAS SOUTH OF I-70.  
 
- HOTTER AND DRIER CONDITIONS THURSDAY AND FRIDAY.  
 
- RETURN TO MORE UNSETTLED PATTERN AND COOLER WEATHER FAVORED FOR  
SUNDAY INTO MONDAY.  
 

 
   
DISCUSSION /THROUGH MONDAY/
 
 
ISSUED AT 1153 AM MDT MON SEP 7 2026  
 
CLOUD COVER MADE FOR A MILD MORNING TODAY, AND HAS ALSO SLOWED THE  
DIURNAL WARMING SOMEWHAT. ACARS SOUNDINGS SHOW ABUNDANT MOISTURE  
STILL IN PLACE (PW ~1" CURRENTLY), AND THIS SHOULD ONLY INCREASE  
AS THE DAY PROGRESSES. INSTABILITY, WHICH IS A NOTCH LOWER THAN  
YESTERDAY, WILL LIKELY BE MAXIMIZED WITHIN THE ZONE OF SOUTHERLY  
FLOW SOUTH AND EAST OF THE DCVZ. THAT SAID, THE AXIS OF BETTER  
SHEAR IS NOT PARTICULARLY COINCIDENT, BEING SHIFTED FARTHER NORTH  
OVER THE I-76 CORRIDOR WHERE FLOW ALOFT WILL BE STRONGER GIVEN  
THE APPROACHING TROUGH AND JET. THIS MAKES IT DIFFICULT TO  
PINPOINT ONE SPECIFIC AREA OF GREATER COVERAGE FOR AFTERNOON  
SHOWERS AND THUNDERSTORMS. IN ANY CASE, SCATTERED SHOWERS LOOK TO  
DEVELOP MID-AFTERNOON OVER THE URBAN CORRIDOR WITH POTENTIAL FOR ISOLATED  
AND MOSTLY WEAK THUNDERSTORMS. THE ENVIRONMENT WOULD SUPPORT SOME  
STRENGTHENING INTO THE EASTERN PLAINS WHERE A FEW STORMS COULD BE  
STRONG TO MARGINALLY SEVERE LATER THIS AFTERNOON AND EVENING.  
TEMPERATURES WILL TREND DOWN FOR MOST AREAS GIVEN INCREASED CLOUD  
COVER AND UPSLOPE FLOW TO THE NORTH OF THE DCVZ, WITH THE WARMEST  
TEMPERATURES FOCUSED OVER OUR SOUTHEAST PLAINS.  
 
THE UPPER-LEVEL TROUGH WILL TRAVERSE THE NORTHERN CONUS TUESDAY,  
PUSHING A WEAK COLD FRONT THROUGH THE PLAINS AND LOWERING  
TEMPERATURES 3-8 DEGREES FOR MOST AREAS. THIS WILL ALSO LEAD TO  
MORE STABLE CONDITIONS AND EROSION OF MOISTURE ACROSS THE NORTHERN  
HALF OF THE FORECAST AREA, REDUCING PRECIPITATION CHANCES  
CONSIDERABLY. AREAS ROUGHLY ALONG AND SOUTH OF I-70, WHERE BETTER  
INSTABILITY, SHEAR AND PW WILL OVERLAP, WILL REMAIN FAVORED FOR  
AFTERNOON CONVECTION AND SOME LOCALLY HEAVY RAIN.  
 
DRIER WESTERLY FLOW WILL SETTLE INTO THE REGION WEDNESDAY AS A  
ZONAL PATTERN TAKES HOLD, POTENTIALLY MAKING WEDNESDAY THE COOLEST  
DAY OF THE WEEK WITH HIGHS IN THE LOW/MID 80'S (ONLY SUNDAY COULD  
CHALLENGE THAT). MOST WILL STAY DRY, THOUGH A CHANCE OF AN  
AFTERNOON SHOWER OR THUNDERSTORM WILL LINGER FOR ELBERT AND  
LINCOLN COUNTIES. THOSE CHANCES EVAPORATE COME THURSDAY AS  
MOISTURE ALOFT DECREASES FURTHER. TEMPERATURES LOOK TO REBOUND  
BACK TO ABOVE-NORMAL VALUES. EXPECT LITTLE CHANGE IN THOSE  
CONDITIONS INTO FRIDAY.  
 
FORECAST CONFIDENCE LOWERS OVER THE COURSE OF THE WEEKEND AS MODELS  
BEGIN TO DIVERGE IN THEIR TREATMENT OF AN AMPLIFYING TROUGH OVER  
THE PACNW. MOST HINT A SUBTLE SHORTWAVE EMBEDDED WITHIN ZONAL FLOW  
ON SATURDAY AND AN ASSOCIATED WEAK COLD FRONT BRINGING INITIALLY  
COOLER TEMPERATURES AND A RETURN OF PRECIPITATION CHANCES. THE  
MORE SIGNIFICANT COOLDOWN HOWEVER WILL LIKELY WAIT UNTIL EITHER  
SUNDAY OR MONDAY, DEPENDING ON THE TIMING OF THE STRONGER FRONT  
AS THE DEEPER TROUGH APPROACHES AND LIFTS THROUGH THE NORTHERN  
ROCKIES. FLOW ALOFT WILL SHIFT BACK TO THE SOUTHWEST STARTING  
SUNDAY WITH A STRENGTHENING JET IN THE MIX AS WELL. AS SUCH, WE  
SHOULD SEE A BETTER WINDOW FOR A RETURN TO UNSETTLED WEATHER AND  
POTENTIALLY SOME STRONGER THUNDERSTORMS AND LOCALLY HEAVY RAIN,  
BUT OF COURSE ALL OF THOSE DETAILS REMAIN QUITE FUZZY.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
 
 
ISSUED AT 1153 AM MDT MON SEP 7 2026  
 
LIGHT NORTHERLY WINDS ARE EXPECTED TO SLOWLY TURN NORTHEAST THEN  
EAST-NORTHEAST OVER THE NEXT SEVERAL HOURS. MOSTLY CLOUDY SKIES  
THIS MORNING HAVE SLOWED WARMING SO FAR TODAY. ACARS SOUNDINGS  
STILL INDICATE A WELL-CAPPED AIRMASS AND VERY LITTLE CAPE.  
SATELLITE IMAGERY SHOWS SOME CLEARING WILL MOVE OVER SOON. DECIDED  
TO KEEP THE PROB30 FOR TS AT DEN AND APA, DUE TO THE  
ANTICIPATED CLEARING AND LIFT FROM THE RIGHT ENTRANCE REGION OF  
THE JET. BEST CHANCE FOR STORMS IS ON TRACK TO BE SOUTH AND EAST  
OF THE DENVER AREA. WIND DIRECTION LATE THIS AFTERNOON/EVENING IS  
EXPECTED TO BE DICTATED BY OUTFLOWS. ONCE CONVECTION ENDS,  
NORTHWEST WINDS ARE EXPECTED TONIGHT DUE TO LOWER SURFACE PRESSURE  
OVER SOUTHEAST COLORADO AND CLOUD COVER WHICH WILL LIMIT COOLING  
AND DISTURB THE TYPICAL DRAINAGE PATTERN.  FOR TUESDAY AFTERNOON,  
WILL INTRODUCE A PROB30 FOR THUNDERSTORMS.   
 

 
   
BOU WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
DISCUSSION...BRQ  
AVIATION...BM  
 
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