510
FXUS65 KGJT 171801
AFDGJT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1101 AM MST WED DEC 17 2025
KEY MESSAGES
- WINTER WEATHER ADVISORIES REMAIN IN EFFECT FOR THE NORTHERN
MOUNTAINS WHERE 3 TO 7 INCHES OF NEW SNOW ABOVE 9000 FEET ARE
EXPECTED, ALONG WITH GUSTY WINDS.
- GUSTY WINDS OF 45 TO 50 MPH WILL BE POSSIBLE FOR PORTIONS OF
THE NORTHERN VALLEYS WHERE WIND ADVISORIES HAVE BEEN ISSUED.
- PERIODS OF LIGHT MOUNTAIN RAIN/SNOW ARE POSSIBLE NORTH OF
INTERSTATE 70 THIS WEEKEND.
SHORT TERM /THROUGH THURSDAY/
ISSUED AT 308 AM MST WED DEC 17 2025
CLOUDS WILL BE ON THE INCREASE THROUGH THE DAY AS MOISTURE FROM
AN ATMOSPHERIC RIVER STARTS TO MOVE INTO THE AREA. THERE IS
LITTLE CHANGE TO THE GOING FORECAST AS A STRONG JET STREAM TAKES
AIM AT THE FORECAST AREA WHILE SUPPORTING A SURFACE COLD FRONT.
THIS JET WILL BE IMPRESSIVE REACHING CLOSE TO 160 KTS AT 250MB
AS IT MOVES OVERHEAD LATER TONIGHT. AS THE COLD FRONT MOVES
THROUGH, SOME DEEPER MIXING WILL ALLOW THESE STRONGER WINDS TO
REACH THE SURFACE. ENSEMBLES ARE IN GOOD AGREEMENT THAT SOME
GUSTS OF 45 TO 50 MPH WILL MOVE INTO EASTERN PORTIONS OF THE
NORTHERN VALLEYS AND THE STEAMBOAT SPRINGS AREA SO ISSUED A WIND
ADVISORY TO ACCOUNT FOR THESE GUSTS LATER THIS AFTERNOON AND
OVERNIGHT. THE HIGHEST ELEVATIONS OF THE CENTRAL AND NORTHERN
MOUNTAINS WILL LIKELY SEE GUSTS OF 50 TO 60 MPH...AN OCCASIONAL
GUST TO 70 MPH CAN'T BE RULED OUT.
ALONG WITH THE GUSTY WINDS, SNOWFALL AMOUNTS OF 3 TO 7 INCHES
ABOVE 9,000 FEET WILL ACCOMPANY COLD FRONTAL PASSAGE SO THE
WINTER WEATHER ADVISORIES REMAIN IN EFFECT. SNOWFALL RATES WILL
BE MAXIMIZED AS THE FRONT MOVES THROUGH AND WITH STRONGER
SURFACE WINDS EXPECTED, TRAVELLING WILL BE DIFFICULT AT TIMES AS
VISIBILITIES DROP QUICKLY IN SNOW SQUALLS. SOME CONVECTION MAY
ALSO ACCOMPANY FRONTAL PASSAGE, DESPITE ANY STRONG CAPE OR
MIDLEVEL INSTABILITY, THANKS TO THE STRENGTH OF THE COLD FRONT
AND UPPER LEVEL SUPPORT.
BY THURSDAY MORNING, SNOW WILL HAVE ENDED THOUGH SOME LINGERING
SNOWSHOWERS MAY PERSIST OVER THE PARK RANGE. THE COLD FRONT
WILL MAKE IT AS FAR SOUTH AS THE SAN JUANS SO LOOK FOR COOLER
HIGHS THURSDAY AND NOT MUCH CHANGE FOR THE SOUTHERN VALLEYS.
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/
ISSUED AT 308 AM MST WED DEC 17 2025
NORTHWESTERLY FLOW WILL ALLOW FOR OROGRAPHIC LIFT IN THE NORTHERN
MOUNTAINS THROUGH THE END OF THE WORKWEEK. INCREASED ATMOSPHERIC
MOISTURE WILL ADVECT THROUGH THE AREA THURSDAY AFTERNOON THROUGH
EARLY FRIDAY. OROGRAPHIC LIFT IS EXPECTED TO PRODUCE LIGHT
PRECIPITATION IN THE NORTHERN TERRAIN FROM THIS MOISTURE PUSH.
FORCING WILL BE PRETTY LIMITED UNTIL THE WEEKEND, SO NOT MUCH IS
ANTICIPATED IN TERMS OF ACCUMULATING SNOW. THE HIGHEST PEAKS OF THE
PARK RANGE MIGHT SEE AN INCH OR TWO BY THURSDAY NIGHT.
RELATIVELY DRIER AIR WILL BRIEFLY MOVE IN DURING THE DAY FRIDAY, BUT
ANOMALOUS ATMOSPHERIC MOISTURE RETURNS FRIDAY NIGHT. NORTHWESTERLY
FLOW IS EXPECTED TO PERSIST, SUPPORTING OROGRAPHIC LIFT. ENERGY FROM
PASSING DISTURBANCES IN THE MEAN FLOW MAY ALSO PROVIDE ADDITIONAL
FORCING. AS SUCH, GREATER SNOW ACCUMULATIONS IN THE NORTHERN
MOUNTAINS ARE ANTICIPATED OVER THE WEEKEND WHEN COMPARED TO
THURSDAY. HOWEVER, THE ECMWF ENS AND GFS ENS DISAGREE ON MOISTURE,
AS THE LATTER SUGGESTS A DECREASE SATURDAY AFTERNOON BEFORE
INCREASING AGAIN SUNDAY MORNING. THE ECMWF FAVORS CONTINUOUS WELL
ABOVE NORMAL MOISTURE VALUES THROUGH THE WEEKEND WITH NO
MAJOR DECREASE.
ABOVE NORMAL TEMPERATURES WILL PERSIST THROUGH THE LONG TERM PERIOD.
BEGINNING FRIDAY, HIGHS ARE EXPECTED TO BE MORE THAN 15 DEGREES
ABOVE NORMAL. THIS MEANS MOST AREAS, WITH THE EXCEPTIONS OF THE
HIGHEST MOUNTAIN PEAKS, WILL REACH ABOVE FREEZING TEMPERATURES
DURING THE DAY. SO, SNOW LEVELS COULD REMAIN ABOVE 8000 FEET FOR
MUCH OF THE WEEKEND.
AVIATION /18Z TAFS THROUGH 18Z THURSDAY/
ISSUED AT 1042 AM MST WED DEC 17 2025
WINDS ALOFT ARE INCREASING WITH LOWER CEILINGS AS A FAST MOVING
STORM SYSTEM COMES IN FROM THE NORTHWEST. EXPECT WIDESPREAD
WIND SHEAR THOUGH MOUNTAIN TAF SITES WITH SURFACE WINDS GUSTING
30 TO 40 KTS AT TIMES. LOWER CEILINGS AND VIS ARE POSSIBLE FOR
KASE, KEGE, KRIL AND KHDN AS SHOWERS MOVE BETWEEN 21Z AND 03Z
AHEAD OF A SURFACE COLD FRONT WITH CONDITIONS BELOW ILS
BREAKPOINTS AS THESE SHOWERS MOVE THROUGH. CONDITIONS IMPROVE
AFTER 06Z WITH CLEARING SKIES AND WINDS DECREASING.
GJT WATCHES/WARNINGS/ADVISORIES
CO...WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 5 AM MST THURSDAY
FOR COZ002-005.
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR
COZ004.
UT...NONE.
SHORT TERM...TGR
LONG TERM...GF
AVIATION...DB
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page