885
FXUS65 KBOU 152231
AFDBOU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
307 PM MST MON DEC 15 2025
KEY MESSAGES
- WARM AND DRY THROUGH TUESDAY, WITH BREEZY CONDITIONS TONIGHT
INTO TUESDAY FOR THE FOOTHILLS AND MOUNTAINS.
- REMAINING WARM WEDNESDAY WITH STRONG WINDS EXPECTED WEST OF I-25.
A HIGH WIND WATCH HAS BEEN ISSUED FOR WEDNESDAY LATE MORNING
THROUGH WEDNESDAY EVENING.
- NEAR-CRITICAL TO CRITICAL FIRE WEATHER ACROSS PORTIONS OF THE
FOOTHILLS AND PLAINS ON WEDNESDAY. A FIRE WEATHER WATCH WILL
BE IN EFFECT FROM LATE WEDNESDAY MORNING THROUGH EARLY
WEDNESDAY EVENING.
- FRIDAY MAY SEE CRITICAL FIRE WEATHER CONDITIONS ACROSS PORTIONS
OF THE PLAINS AND URBAN CORRIDOR.
- LIGHT MOUNTAIN SNOW POTENTIAL WEDNESDAY INTO THURSDAY AND FRIDAY
INTO THE WEEKEND.
SHORT TERM /THROUGH MONDAY/
ISSUED AT 213 PM MST SUN DEC 14 2025
UPPER LEVEL RIDGING OVER COLORADO FLATTENS DURING THE DAY MONDAY AS
NORTHWEST FLOW ALOFT BEGINS TO INCREASE. FOR TONIGHT, WEST WINDS IN
THE HIGHER FOOTHILLS AND FRONT RANGE MOUNTAINS INCREASE, WITH GUSTS
TO 40 MPH POSSIBLE. ELSEWHERE, WE ARE LOOKING AT RELATIVELY LIGHT
WINDS. TEMPERATURES IN THE MOUNTAIN VALLEYS AND LOWER LYING AREAS
ACROSS THE PLAINS WILL BE COOLER SPOTS, WITH LOWS IN THE TEENS AND
LOWER 20S. ON MONDAY, IT WILL BE MILD AGAIN WITH TEMPERATURES WELL
ABOVE NORMAL. HIGH ACROSS NORTHEAST COLORADO WILL REACH THE UPPER
50S TO MID 60S. CROSS SECTIONS SHOW SOME HIGH LEVEL MOISTURE, MAINLY
DURING THE MORNING, WITH DECREASING HIGH CLOUDS DURING THE
AFTERNOON. EXPECT FOR THOSE TYPICAL BREEZY LOCATIONS IN THE
FOOTHILLS AND MOUNTAINS, LIGHT WINDS WILL PREVAIL MONDAY.
LONG TERM /TUESDAY NIGHT THROUGH MONDAY/
ISSUED AT 302 PM MST MON DEC 15 2025
STRONG WINDS WILL RETURN TO THE MOUNTAINS AND POTENTIALLY THE
I-25 CORRIDOR ON WEDNESDAY. THE MID AND UPPER LEVEL FLOW WILL
INCREASE ALONG THE FRONT RANGE WEDNESDAY MORNING AND INTO THE
AFTERNOON. WINDS ARE FORECAST TO PEAK WEDNESDAY AFTERNOON AND
EVENING WITH CROSS BARRIER FLOW AROUND 60 TO 70KTS AT MOUNTAIN
TOP. WIND GUSTS IN THE HIGHER ELEVATIONS COULD APPROACH 90 MPH AT
TIMES WEDNESDAY AFTERNOON. THE SOUNDINGS FROM THE GLOBAL MODELS
ARE MISSING A CRITICAL LAYER AND THE INVERSION ABOVE RIDGE TOP IS
NOT AT THE IDEAL LEVEL FOR A DOWNSLOPING EVENT, BOTH OF WHICH WILL
HINDER THE WINDS ABILITY TO PUSH EASTWARD INTO THE LOWER
FOOTHILLS AND SURROUNDING PLAINS. HOWEVER, SOME OF THE HIGHER RES
MODELS, LIKE THE RRFS, ARE STARTING TO SHOW BOTH A CRITICAL LAYER
AND INVERSION, WHICH HELPS INCREASE OUR CONFIDENCE THAT STRONGER
WINDS COULD MOVE FURTHER EAST INTO THE I-25 CORRIDOR WEDNESDAY
AFTERNOON. ALSO, A FEW ENSEMBLE MEMBERS OF BOTH THE GEFS AND
EUROPEAN ARE SHOWING GUSTS IN THE 60 TO 75MPH RANGE IN THE
FOOTHILLS AND AT THE BASE OF THE FOOTHILLS. WE'LL GET A BETTER
IDEA ON THE POTENTIAL FOR THE WINDS TO PUSH FURTHER EAST AS THE
HIGH RES MODELS CONTINUE TO COME IN AND WE'LL CONTINUE TO KEEP AN
EYE ON THE POTENTIAL FOR A CRITICAL LAYER AND INVERSION.
ANOTHER THING TO WATCH FOR WEDNESDAY IS THE COLD FRONT MOVING IN
FROM THE NORTHWEST WEDNESDAY EVENING AND OVERNIGHT. JUST AHEAD OF
THE FRONT, WE COULD SEE MOUNTAIN WAVE ENHANCEMENT, WHICH WOULD HELP
GIVE THE WINDS THE EXTRA PUSH THEY NEED TO REACH BOULDER AND WEST
METRO DENVER. AS THE FRONT MOVES IN, THE WINDS WILL TURN FROM A
CHINOOK EVENT INTO MORE OF A BORA EVENT, WITH DECENT NORTHWEST WINDS
BEHIND THE FRONT. RIGHT NOW, WINDS BEHIND THE FRONT LOOK TO STAY
AROUND 20 TO 30MPH WITH GUSTS AROUND 40MPH. HOWEVER, THE GFS DOES
KEEP WINDS A BIT HIGHER BEHIND THE FRONT, WITH SOME SUSTAINED SPEEDS
CLOSER TO 40MPH. TEMPERATURES WILL BE COOLER AND MUCH CLOSER TO
NORMAL FOR THURSDAY AFTERNOON THANKS TO THE FRONT. RH IS EXPECTED
TO DROP TO 15-20% ACROSS THE I-25 CORRIDOR. WITH THE POTENTIAL FOR
HIGH WINDS SEVERAL HOURS WEDNESDAY AFTERNOON, THERE ARE SIGNIFICANT
FIRE WEATHER CONCERNS COVERED IN IN THE FIRE WEATHER DISCUSSION
BELOW.
WINDS WILL PICK BACK UP THURSDAY NIGHT INTO FRIDAY. WIND GUSTS AT
HIGHER ELEVATIONS COULD BE IN THE 70 TO 90MPH RANGE AGAIN FRIDAY
MORNING. ONCE AGAIN, WE HAVE LOWER CERTAINTY IN HOW FAR EAST THE
STRONGER WINDS WILL PUSH. RIGHT NOW, WE'RE KEEPING THE STRONGER WIND
GUSTS (50+MPH) GENERALLY ABOVE 7000FT. WITH THE DOWNSLOPING WINDS
AGAIN ON FRIDAY, TEMPERATURES WILL WARM BACK UP TO POTENTIALLY
RECORD BREAKING HIGHS. WEAKER DOWNSLOPING WINDS AND THE APPROACH OF
A LOW PRESSURE SYSTEM AND COLD FRONT WILL KEEP TEMPERATURES A FEW
DEGREES COOLER FOR THE WEEKEND, BUT HIGHS WILL REMAIN WELL ABOVE
NORMAL.
NOW ONTO PRECIP CHANCES. THE MOUNTAINS WILL HAVE A FEW CHANCES AT
SNOW THIS WEEK. THE FIRST ROUND WILL BE ASSOCIATED WITH THE STRONG
WEST UPSLOPE FLOW, DECENT MOISTURE, AND FRONTAL PASSAGE WEDNESDAY
INTO THURSDAY. THE HIGHER ELEVATIONS OF THE FRONT RANGE AND PARK
RANGE COULD SEE A AROUND 2 TO 6 INCHES OF SNOW, WITH SOME HIGHER
AMOUNTS ON THE PEAKS. THE FOOTHILLS AND PLAINS ALSO HAVE A CHANCE OF
PRECIP WITH THE FRONTAL PASSAGE, BUT CHANCES WILL BE LOW (<30%) AND
IT SHOULD BE PRIMARILY LIGHTER RAIN AMOUNTS. THE NEXT CHANCE FOR
PRECIPITATION IN THE MOUNTAINS WILL BE FRIDAY THROUGH SUNDAY. THE
FRONT AND PARK RANGES COULD SEE AN ADDITIONAL FEW INCHES WITH THIS
ACTIVITY.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1038 AM MST MON DEC 15 2025
VFR CONDITIONS ARE EXPECTED THROUGH THIS TAF PACKAGE. WINDS ARE
EXPECTED TO REMAIN LESS THAN 12KTS THROUGH THIS EVENING AND
OVERNIGHT AT ALL TAF SITES. WINDS AT KDEN WILL GENERALLY BE FROM
THE SOUTHEAST THIS AFTERNOON, BEFORE TURNING TOWARDS DRAINAGE FLOW
THIS EVENING. ALL TAF SITES WILL HAVE LIGHT SOUTHWEST DRAINAGE
FLOW DURING THE OVERNIGHT PERIOD. WINDS WILL THEN BECOME VARIABLE
AT KDEN LATE TOMORROW MORNING BEFORE TURNING EAST FOR TOMORROW
AFTERNOON.
FIRE WEATHER
ISSUED AT 302 PM MST MON DEC 15 2025
STRONG DOWNSLOPING WINDS AND MARGINAL RELATIVE HUMIDITY VALUES
WILL LEAD TO NEAR CRITICAL TO CRITICAL FIRE WEATHER WEDNESDAY
AFTERNOON. MINIMUM RH VALUES WILL BE AROUND 15 TO 30% IN THE
FOOTHILLS AND THE PLAINS. WIND GUSTS WEDNESDAY AFTERNOON COULD
APPROACH 60MPH AT TIMES IN THE I-25 CORRIDOR. WINDS WILL BE
LIGHTER AND RH HIGHER ON THURSDAY, LIMITING FIRE WEATHER
POTENTIAL. WINDS WILL INCREASE INTO THE 15 TO 30MPH RANGE FOR
FRIDAY. MINIMUM RH VALUES FRIDAY WILL DROP TO 13 TO 25%, LEADING
TO ELEVATED TO NEAR- CRITICAL FIRE WEATHER. SMOKE DISPERSAL
CONDITIONS WILL BE FAIR TO VERY GOOD FOR THE WEST SLOPE MOUNTAIN
VALLEYS WEDNESDAY THROUGH SATURDAY.
BOU WATCHES/WARNINGS/ADVISORIES
HIGH WIND WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING
FOR COZ033>036-038-039.
FIRE WEATHER WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
AFTERNOON FOR COZ238>240-242-243-245.
SHORT TERM.....12
LONG TERM...AP
AVIATION...AP
FIRE WEATHER...AP
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