782
FXUS65 KBOU 111131
AFDBOU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
531 AM MDT THU SEP 11 2025
KEY MESSAGES
- ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS THE NEXT FEW
DAYS, WITH HIGHER CHANCES OF RAINFALL BY FRIDAY OR SATURDAY.
- VERY WARM TODAY, WITH ANOTHER 90F DAY POSSIBLE ON THE PLAINS AND
I-25 CORRIDOR. COOLER TEMPERATURES THIS WEEKEND INTO NEXT WEEK.
UPDATE
ISSUED AT 839 PM MDT WED SEP 10 2025
MINOR UPDATE FOR LINGERING POPS AND A BIT MORE WIND ON THE PLAINS.
CURRENT STORM TRACKING ALONG I-80 IN THE PANHANDLE COULD CROSS THE
BORDER, BUT WILL MORE LIKELY STAY IN NEBRASKA AND WEAKEN. THERE'S
ALSO SOME SHALLOW CONVECTION TRYING TO BREAK OUT IN MORGAN COUNTY
AT THIS TIME. PLENTY OF MOISTURE AND SOUTHEAST INFLOW (SURFACE
WINDS HAVE PROBABLY DROPPED DUE TO DECOUPLING) THAT COULD FEED
STORMS IN A MARGINAL ENVIRONMENT THROUGH MIDNIGHT OR SO. STORMS
OVER THE ROCKY MOUNTAIN NATIONAL PARK AREA RIGHT NOW PROBABLY
WON'T SURVIVE EAST OF THE MOUNTAINS, ALTHOUGH THERE COULD BE A
LITTLE LEFT SINCE THE SOUTHEAST WINDS AND MOISTURE ARE GETTING
INTO THAT AREA NOW.
DISCUSSION /THROUGH WEDNESDAY/
ISSUED AT 243 PM MDT WED SEP 10 2025
IT'S A WARM ONE OUT THERE THIS AFTERNOON. TEMPERATURES ACROSS MOST
OF THE DENVER METRO HAVE MADE IT INTO THE UPPER 80S TO LOW 90S.
DEN RECENTLY HIT 90F, AND WE'VE ALSO SEEN THAT NUMBER AT CENTRAL
PARK (90F), AND THE ARSENAL RAWS (92F), AND KBKF/KCFO/KBJC ALONG
WITH NUMEROUS UNOFFICIAL STATIONS. WITH ANOTHER HOUR OR TWO OF
POTENTIAL WARMING, WE'LL SEE IF WE MANAGE ANOTHER DEGREE OR TWO OF
WARMING ACROSS THE METRO. MEANWHILE, A FEW WEAK SHOWERS AND
PERHAPS A THUNDERSTORM OR TWO WILL BE POSSIBLE THROUGH THE REST OF
THE AFTERNOON, THOUGH GIVEN THE DRY AIRMASS AND MEAGER
INSTABILITY, COVERAGE OF STORMS SHOULD BE LIMITED.
THE FORECAST THROUGH THE REST OF THE WORK WEEK SHOULD BE
RELATIVELY STRAIGHTFORWARD, AS A LARGE UPPER TROUGH AXIS DRIFTS
FROM THE INTERMOUNTAIN NORTHWEST INTO THE NORTHERN ROCKIES.
SOUTHWESTERLY FLOW ALOFT WILL GRADUALLY INCREASE WITH BETTER
MOISTURE ALSO SLOWLY STREAMING INTO THE REGION. MOST GUIDANCE
KEEPS THE BETTER MOISTURE ACROSS SOUTHWESTERN COLORADO, AND IT'S
NO SURPRISE THE BETTER POPS/QPF ARE ACROSS OUR MOUNTAINS AND WEST
INTO THE GJT FORECAST AREA. A FEW STRONGER STORMS ARE POSSIBLE
TOMORROW WITH SOME OVERLAP OF DEEP LAYER SHEAR AND MLCAPE... BUT
THE POTENTIAL FOR WIDESPREAD/ORGANIZED SEVERE WEATHER LOOKS LOW.
AS THE TROUGH EVENTUALLY LIFTS NORTHEASTWARD, WE SHOULD SEE AT
LEAST ONE OR TWO SHORTWAVES ROUND THE BASE OF THE TROUGH AND TRACK
ACROSS COLORADO. THERE'S STILL A DECENT AMOUNT OF SPREAD ACROSS
GUIDANCE, WITH THE GFS/GEFS ON THE FASTER SIDE AND THE VARIOUS
ECMWF PRODUCTS A TOUCH SLOWER. WHETHER FRIDAY OR SATURDAY WOULD BE
THE FAVORED DAY FOR RAIN ACROSS THE LOWER ELEVATIONS IS STILL UP
IN THE AIR, BUT THERE IS STILL BROAD AGREEMENT THAT WE'LL MANAGE
ONE DAY OF DECENT (>40%) CHANCES OF RAIN FOR THE DENVER METRO. THE
TROUGH PASSAGE SHOULD ALSO IN SOME SLIGHTLY COOLER TEMPERATURES,
ALTHOUGH "COOLER" IN THE CASE WILL JUST MEAN "NEAR NORMAL" WITH
HIGHS IN THE UPPER 70S TO LOW 80S.
MODEL SOLUTIONS SLOWLY BEGIN TO DIVERGE AS WE GET INTO NEXT WEEK,
WITH LESS CONSISTENCY HANDLING A FAIRLY COMPLEX UPPER LEVEL
PATTERN. THERE'S BROAD AGREEMENT FOR A BRIEF WARMUP TO START NEXT
WEEK, BUT DETAILS BEYOND THAT ARE MUCH MORE HAZY.
AVIATION /12Z TAFS THROUGH 12Z FRIDAY/
ISSUED AT 530 AM MDT THU SEP 11 2025
VFR THROUGH THE TAF PERIOD. MAIN CONCERN IS ONCE AGAIN A PERIOD
OF GUSTY/VARIABLE WINDS DUE TO RELATIVELY HIGH BASED SHOWER/STORM
OUTFLOWS THIS AFTERNOON AND EVENING. COVERAGE AND THEREFORE THE
PROBABILITY OF -TSRA AND VRB WINDS TAKES A SLIGHT INCREASE FROM
YESTERDAY DUE TO A SLIGHT UPTICK IN OVERALL MOISTURE, BUT NOT
ENOUGH TO GO ANY MORE THAN A PROB30 AT THIS TIME. MAIN TIME FRAME
OF CONCERN WOULD AGAIN BE FROM 21Z-02Z.
OTHERWISE WINDS SHOULD START FROM THE W-SW THROUGH ABOUT 17Z, AND
THEN BECOME VARIABLE. THERE IS MORE UNCERTAINTY AS TO HOW WINDS
THEN PROGRESS THROUGH 21Z, BUT MOST LIKELY IS A NORTHEAST OR
EASTERLY COMPONENT DEVELOPING BEFORE SHOWER/STORM OUTFLOWS START
TO DISRUPT WINDS. MODELS THEN SUGGEST A RATHER QUICK RETURN TO SSW
AROUND 12 KTS 02-04Z AFTER CESSATION OF ANY SHOWERS OR STORMS IN
THE VICINITY.
BOU WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...GIMMESTAD
DISCUSSION...HIRIS
AVIATION...BARJENBRUCH
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page