864  
FXUS65 KBOU 210001  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
601 PM MDT FRI MAR 20 2026  
   
KEY MESSAGES  
 
 
- ALL-TIME MARCH RECORD HIGH TEMPERATURES BROKEN ON THURSDAY WILL  
ALMOST CERTAINLY BE BROKEN ONE OR TWO MORE TIMES THROUGH  
SATURDAY.  
 
- HEAT PEAKS ON SATURDAY WITH ALL TIME MARCH RECORDS BEING BROKEN  
BY SEVERAL DEGREES! A FEW LOCATIONS MAY SEE 90F SATURDAY  
AFTERNOON.  
 
- PROLONGED ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS DUE TO  
RECORD HEAT AND EXTREMELY LOW HUMIDITY LEVELS. SATURDAY IS STILL  
SHAPING UP TO BE THE MOST WIDESPREAD CRITICAL DAY AS WINDS  
INCREASE.  
 
- BRIEF DROP TO NEAR NORMAL TEMPERATURES SUNDAY.  
 
- RETURN OF UNSEASONABLE WARMTH, POTENTIAL RECORD HEAT (>70%  
CHANCE), AND MORE FIRE WEATHER CONCERNS AGAIN BY TUESDAY AND  
WEDNESDAY.  
 
 
   
DISCUSSION /THROUGH FRIDAY/  
 
ISSUED AT 145 PM MDT FRI MAR 20 2026  
 
THERE'S ONLY SO MUCH WE CAN WRITE ABOUT WITH THE ONGOING PATTERN.  
A RELENTLESS UPPER LEVEL RIDGE CONTINUES TO SIT OVER THE DESERT  
SOUTHWEST, BUT WILL START TO FLATTEN LATER TODAY INTO SATURDAY.  
HIGH TEMPERATURES WILL END UP NEAR ALL-TIME RECORD HIGHS FOR  
MARCH (AND, IN SOME CASES WOULD BE RECORD HIGHS FOR APRIL!)  
THROUGH SATURDAY.  
 
THE FLATTENING UPPER LEVEL RIDGE WILL LEAD TO INCREASING ZONAL  
FLOW ALOFT... LEADING TO AN ADDED DOWNSLOPE COMPONENT TO THE  
LOW/MID-LEVEL FLOW AS THOSE WINDS MIX DOWN LATE SATURDAY MORNING  
INTO SATURDAY AFTERNOON. MID-LEVEL TEMPERATURES ARE EXPECTED TO  
WARM ANOTHER ~2C (NEAR +14-15C), WHICH WOULD TRANSLATE TO HIGH  
TEMPERATURES ABOUT 5F WARMER THAN YESTERDAY/TODAY. EXACTLY HOW  
MUCH WIND MIXES DOWN SATURDAY WILL DETERMINE IF WE DO SEE A  
COUPLE >90F TEMPERATURES ACROSS THE PLAINS, AND WILL ALSO HAVE  
IMPLICATIONS FOR FIRE WEATHER CONCERNS ACROSS THE LOWER  
ELEVATIONS. UNFORTUNATELY, THERE ISN'T A WELL-DEFINED SIGNAL FOR  
THIS ACROSS TODAY'S GUIDANCE. THE HRRR/RRFS SOLUTIONS ARE  
GENERALLY FAVORED IN THIS PERIOD... WHERE WINDS MAY BE SLOW TO  
DEVELOP ACROSS THE PLAINS BUT DO PICK UP ENOUGH BY THE MID-  
AFTERNOON FOR AT LEAST A FEW 90S ACROSS THE DENVER METRO.  
 
WE'LL SEE SOME RELIEF FROM THE HEAT SATURDAY NIGHT AS A COLD FRONT  
PUSHES ACROSS THE PLAINS, LEADING TO A MORE MILD (BUT STILL ABOVE  
NORMAL) TEMPERATURE FORECAST FOR SUNDAY. HIGHS ARE EXPECTED TO  
REMAIN IN THE UPPER 60S TO LOW 70S. GUIDANCE HAS GENERALLY BACKED  
OFF ON THE AMOUNT OF MOISTURE TO WORK WITH, WITH LITTLE (IF ANY)  
PRECIPITATION EXPECTED ACROSS THE HIGHER ELEVATIONS.  
 
RIDGING WILL START TO BUILD BACK ACROSS THE SOUTHWESTERN CONUS  
BY EARLY NEXT WEEK, WITH COLORADO REMAINING ON THE  
NORTH/NORTHEASTERN PERIPHERY OF THE THERMAL RIDGE. MODEST WEST-  
NORTHWEST FLOW ALOFT SHOULD ALLOW FOR AT LEAST A LITTLE ADDED  
WARMING FROM DOWNSLOPE WINDS... WITH HIGHS IN THE 70S ON MONDAY,  
NEAR 80F TUESDAY, AND POTENTIALLY AS WARM AS THE MID/UPPER 80S ON  
WEDNESDAY. NBM PROBABILISTIC/PERCENTILE DATA APPEARS TO BE,  
SOMEWHAT INEXPLICABLY, FAR WARMER THAN THE DETERMINISTIC NBM AND  
MOST OF THE AVAILABLE 12Z ENSEMBLE MEMBERS. OUR FORECAST LIES ON  
THE COOL SIDE OF THE NBM FORECAST, BUT IS PROBABLY A LITTLE  
WARMER THAN IT SHOULD BE.  
 
THERE ARE MIXED SIGNALS BY LATER IN THE WEEK. ANOTHER SHORTWAVE  
DOES ATTEMPT TO IMPINGE ON THE RIDGE BY THURSDAY OR FRIDAY, WITH  
MOST GUIDANCE ATTEMPTING TO PUSH ANOTHER COLD FRONT IN THURSDAY.  
HOWEVER, THERE APPEARS TO BE A GRADUAL TREND TO HOLD ONTO THE  
ABOVE NORMAL TEMPERATURES THROUGH THURSDAY. THAT SHORTWAVE MAY  
HAVE ENOUGH MOISTURE ASSOCIATED WITH IT FOR A FEW SCATTERED  
RAIN/SNOW SHOWERS ACROSS THE HIGHER ELEVATIONS, BUT ENSEMBLE  
GUIDANCE CONTINUES TO LOOK RATHER DRY THROUGH THE END OF THE  
MONTH.  
 
 
   
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/  
 
ISSUED AT 537 PM MDT FRI MAR 20 2026  
 
VFR TO PERSIST THROUGH THE TAF PERIOD. WINDS HAVE LARGELY REMAINED  
LIGHT ACROSS THE TAF SITES TODAY OUTSIDE OF SOME STRONGER WESTERLY  
GUSTS MAKING THEIR WAY INTO KBJC. RADAR SHOWED SOME OF THOSE GUSTS  
MAKE IT JUST WEST OF KDEN'S AIRFIELD OVER THE PAST HOUR, BUT THEY  
DIDN'T HAVE QUITE ENOUGH UMPF AND THINGS ARE ALREADY TRENDING TO  
THE EXPECTED EASTERLY DIRECTION. STILL ON TRACK TO SEE A  
SOUTHEAST TO SOUTH TRANSITION BETWEEN NOW AND 3-4Z AT KDEN/KAPA,  
WITH WESTERLY WINDS HOLDING ON AT KBJC THROUGH THE OVERNIGHT  
HOURS, THOUGH THERE MAY BE SOME PERIODS OF LIGHT AND VARIABLE  
MIXED IN WITH THE WESTERLIES.  
 
FOR TOMORROW, SOUTHERLY WINDS ARE EXPECTED IN THE MORNING WITH  
EVEN A FEW HOURS OF LIGHT AND VARIABLE POSSIBLE ACROSS ALL THE  
TAF SITES BEFORE GUSTY WEST TO WNW WINDS MIX DOWN IN THE LATE  
AFTERNOON. KBJC SHOULD BE THE FIRST TO SEE THE GUSTY WINDS BY  
20-22Z FOLLOWED BY KAPA THEN KDEN BY 22-23Z.  
 
SHOULD SEE A FEW HOURS OF DRAINAGE WINDS TOMORROW NIGHT BEFORE A  
COLD FRONT SLIDES SOUTH ACROSS THE TAF SITES AND TURNS WINDS TO  
THE NORTH, JUST OUTSIDE OF THIS TAF PERIOD.  
 
 
   
FIRE WEATHER  
 
ISSUED AT 145 PM MDT FRI MAR 20 2026  
 
ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS WILL CONTINUE THROUGH  
THIS EVENING, AND BECOME MORE WIDESPREAD ON SATURDAY. RED FLAG  
CONDITIONS HAVE BEEN OBSERVED AT THE BUCKEYE RAWS AND AT THE AWOS  
SITES LOCATED AROUND THE PAWNEE GRASSLANDS, AND THIS SHOULD  
CONTINUE THROUGH THE REST OF THE AFTERNOON HOURS.  
 
AS ZONAL FLOW INCREASES ON SATURDAY, WIDESPREAD CRITICAL FIRE  
WEATHER CONDITIONS ARE EXPECTED TO DEVELOP. WINDS WILL FIRST START  
TO MIX DOWN TO THE SURFACE ACROSS THE HIGH MOUNTAIN VALLEYS AND  
FRONT RANGE FOOTHILLS BY MID/LATE MORNING, BEFORE SPREADING  
EASTWARD INTO THE I-25 CORRIDOR AND PLAINS BY EARLY/MID AFTERNOON.  
THERE IS SOME QUESTION AS TO HOW FAR EAST WINDS MANAGE TO SPREAD,  
WITH THE I-76 CORRIDOR SERVING AS THE GENERAL CUTOFF POINT FOR RED  
FLAG CONDITIONS.  
 
A COLD FRONT SHOULD BRING A BRIEF PERIOD OF IMPROVED CONDITIONS  
SATURDAY NIGHT AND SUNDAY, BUT WELL ABOVE NORMAL (POTENTIALLY  
RECORD HIGH) TEMPERATURES ARE EXPECTED TO REDEVELOP NEXT WEEK.  
ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS WILL BE POSSIBLE EACH  
AFTERNOON, DEPENDING ON HOW MUCH WIND SPREADS ACROSS THE FORECAST  
AREA.  
 
 
   
BOU WATCHES/WARNINGS/ADVISORIES  
 
RED FLAG WARNING FROM 11 AM TO 10 PM MDT SATURDAY FOR COZ211-  
213>216.  
 
RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ238-242.  
 
RED FLAG WARNING FROM 2 PM TO 10 PM MDT SATURDAY FOR COZ238>245-  
248-250.  
 
 
 
 
 
DISCUSSION...HIRIS  
AVIATION...9  
FIRE WEATHER...HIRIS  
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