923  
FXUS65 KBOU 082328  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
528 PM MDT TUE SEP 8 2026  
   
KEY MESSAGES
 
 
- SLIGHTLY COOLER TODAY WITH A CHANCE OF THUNDERSTORMS MAINLY OVER  
THE PALMER DIVIDE AND SOUTHEAST PLAINS. A FEW STRONG STORMS  
POSSIBLE WITH GUSTY WINDS, HAIL, AND LOCALLY HEAVY RAINFALL.  
 
- MAINLY DRY WEDNESDAY THROUGH FRIDAY WITH WARMER TEMPERATURES FOR  
THURSDAY AND FRIDAY.  
 
- RETURN TO MORE UNSETTLED PATTERN AND COOLER WEATHER FAVORED FOR  
NEXT WEEKEND WITH A CHANCE OF THUNDERSTORMS EACH AFTERNOON.  
 

 
   
DISCUSSION /THROUGH TUESDAY/
 
 
ISSUED AT 1152 AM MDT TUE SEP 8 2026  
 
UPPER-AIR MAPS SHOW AN UPPER-LEVEL LOW COMING OFF THE NORTHERN  
ROCKIES ALONG THE CANADIAN BORDER THIS MORNING, WITH ANOTHER  
SHORTWAVE CLOSE ON ITS HEELS EXPECTED TO MOVE OVER THE NORTHERN  
ROCKIES LATER TODAY. AN ASSOCIATED COLD FRONT MADE ITS WAY INTO  
COLORADO EARLY THIS MORNING THAT IS KEEPING TEMPERATURES AROUND  
FIVE TO TEN DEGREES COOLER THAN MONDAY MORNING. THIS SHOULD KEEP  
AFTERNOON HIGH TEMPERATURES SLIGHTLY COOLER THAN YESTERDAY, WITH  
ONLY A FEW PLACES ACROSS THE PLAINS EXPECTED TO APPROACH THE 90  
DEGREE MARK. THE PERSISTENT UPPER-LEVEL RIDGE OVER THE SOUTH  
CENTRAL CONUS WILL CONTINUE TO PULL A PLUME OF MONSOONAL MOISTURE  
INTO SOUTHEASTERN COLORADO AND KEEP PWATS AROUND 160% OF NORMAL  
ALONG THE SOUTHERN PORTION OF OUR FORECAST AREA. AREAS EXPECTED TO  
SEE THE BEST PRECIPITATION CHANCES WILL GENERALLY BE ALONG AND  
SOUTH OF I-70, WITH POTENTIAL FOR SOME STRONG TO SEVERE STORMS  
OVER THE PALMER DIVIDE AND ACROSS LINCOLN COUNTY THIS EVENING.  
WITH PW VALUES AROUND 1-1.5" EXPECTED, WE COULD GET A FEW HEAVY  
RAINERS THAT COULD LEAD TO LOCALIZED FLASH FLOODING POTENTIAL, AND  
EXPECT AT LEAST AN ISOLATED SEVERE WIND THREAT, MAINLY FOR ELBERT  
AND LINCOLN COUNTIES. THE HREF GUIDANCE HONES IN ON SOUTHERN  
LINCOLN COUNTY LIKELY TO SEE THE GREATEST RAINFALL ACCUMULATIONS,  
WITH THE BEST TIMING OF HEAVIEST RAINFALL AND STRONG WINDS BETWEEN  
7PM-10PM. STORMS SHOULD MOVE OUT OF THE FORECAST AREA BY AROUND  
MIDNIGHT TONIGHT.  
 
ANOTHER COLD FRONT IS EXPECTED ACROSS NORTHERN COLORADO EARLY  
WEDNESDAY MORNING THAT WILL COOL TEMPERATURES BY A FEW MORE  
DEGREES FOR WEDNESDAY AFTERNOON. EXPECT SOME GUSTY NORTHERLY WINDS  
TO MOVE FROM NORTH TO SOUTH ACROSS THE PLAINS AROUND SUNRISE  
FOLLOWED BY COMFORTABLE AFTERNOON HIGH TEMPERATURES AT OR SLIGHTLY  
BELOW NORMAL. THE COOLER AIR ISN'T EXPECTED TO MAKE IT INTO THE  
HIGHER ELEVATIONS, SO OUR MOUNTAIN VALLEYS WILL LIKELY STILL SEE  
ABOVE-NORMAL AFTERNOON HIGH TEMPS, BUT STILL A FEW DEGREES COOLER  
THAN TODAY. MID-LEVEL FLOW ALOFT IS EXPECTED TO BECOME MORE ZONAL  
AS THE SHORTWAVE PASSES TO THE NORTH. THIS WILL MOVE DRIER AIR  
FROM THE WEST INTO THE FORECAST AREA, LIMITING THE MONSOONAL PLUME  
TO SOUTHEASTERN COLORADO. MOSTLY DRY CONDITIONS ARE EXPECTED FOR  
THE FORECAST AREA OUTSIDE OF POTENTIAL FOR SOME SHOWERS IN  
SOUTHERN LINCOLN COUNTY OVERNIGHT.  
 
ZONAL FLOW ALOFT IS EXPECTED TO PERSIST INTO THURSDAY KEEPING  
DRIER AIR FLOWING INTO THE FORECAST AREA. 700 MB TEMPERATURES  
SHOULD WARM BY A FEW DEGREES RESULTING IN AFTERNOON HIGHS ABOUT  
FIVE TO TEN DEGREES ABOVE NORMAL ACROSS THE FORECAST AREA, BUT DRY  
CONDITIONS ARE EXPECTED. WILL HAVE TO WATCH FOR ELEVATED FIRE  
WEATHER CONDITIONS DEVELOPING FOR A FEW HOURS IN NORTH PARK  
THURSDAY AFTERNOON WHERE SINGLE DIGIT RELATIVE HUMIDITY VALUES  
ARE EXPECTED WITH WIND GUSTS APPROACHING CRITICAL THRESHOLDS. FRIDAY  
WILL WARM BY A FEW MORE DEGREES AND LATEST GUIDANCE SUGGESTS A  
SLIGHT INCREASE IN MID-LEVEL MOISTURE IN WNW FLOW MAY BRING  
ISOLATED AFTERNOON SHOWERS, BUT MOST AREAS ARE EXPECTED TO REMAIN  
DRY.  
 
THE NORTHERN TIER LOOKS TO REMAIN FAIRLY ACTIVE THROUGH THE LATTER  
HALF OF THE PERIOD WITH MULTIPLE DISTURBANCES EXPECTED TO MOVE  
ACROSS THE NORTHERN ROCKIES. THIS WILL SEND A FEW MORE COLD FRONTS  
SOUTH ACROSS COLORADO THIS WEEKEND AND EARLY NEXT WEEK. GUIDANCE  
IS STILL DIVERGING ON THE STRENGTH AND TIMING OF A MORE PRONOUNCED  
TROUGH MOVING OUT OF THE PACIFIC NORTHWEST THIS WEEKEND, BUT FOR  
NOW IT'S LOOKING LIKE COOLER TEMPERATURES AND MORE ACTIVE WEATHER  
CAN BE EXPECTED FOR NEXT WEEKEND.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
 
 
ISSUED AT 525 PM MDT TUE SEP 8 2026  
 
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. AS OF 2325Z,  
RADAR SHOWS A THUNDERSTORM CLIPPING THE SOUTHERN SIDE OF KDEN AS  
WELL AS SOME LIGHTER RAIN SHOWERS NEAR KBJC AND KAPA. WE HAVE KEPT  
THE PROB30 AT KDEN THROUGH 1Z TO ACCOUNT FOR THIS CURRENT SHOWER  
AS WELL AS THE LOW CHANCE THAT ANOTHER SHOWER DEVELOPS BEHIND THE  
CURRENT ONE. CAMS CLEAR THE SHOWERS AND THUNDERSTORMS FROM ALL  
THREE TERMINALS BY 2Z. BEHIND THESE SHOWERS, WINDS WILL QUICKLY  
TURN TO THE SOUTHEAST AND THEN SOUTH (DRAINAGE) LATER IN THE  
EVENING.  
 
MODELS REMAIN IN GOOD AGREEMENT OF THE COLD FRONT ARRIVING  
BETWEEN 11Z AND 13Z, WHICH WILL BRING NORTHERLY WINDS TO THE  
TERMINALS. SHORT-TERM MODELS CONTINUE TO HINT AT A BRIEF PERIOD OF  
GUSTIER NORTHERLY WINDS IN THE MORNING FOR DEN, WHERE A TEMPO IS  
IN PLACE BETWEEN 13Z AND 15Z. EXPECT A TYPICAL DIURNAL PATTERN  
TOMORROW AFTERNOON. WITH DRIER AIR FILTERING IN, NO PRECIPITATION  
IS EXPECTED FOR THE TERMINALS TOMORROW AFTERNOON. WINDS WILL TURN  
TO SOUTHEAST AFTER SUNSET TOMORROW.  
 

 
   
BOU WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
DISCUSSION...9  
AVIATION...MV  
 
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