933
FXUS65 KGJT 212343
AFDGJT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
543 PM MDT MON OCT 21 2024
KEY MESSAGES
- COLD AIR SETTLING IN BEHIND THE SYSTEM AS CONDITIONS DRY AND
CLEAR WILL LEAD TO POTENTIAL FOR FREEZING TEMPERATURES IN
SOME OF THE SOUTHERN VALLEYS, NORTHERN VALLEYS AND HIGHER
CENTRAL VALLEYS TONIGHT INTO TUESDAY MORNING.
- DRY CONDITIONS PERSIST THROUGH THE REST OF THIS WEEK WITH A
WARMING TREND BACK TOWARDS WELL ABOVE NORMAL TEMPERATURES.
SHORT TERM /THROUGH TUESDAY NIGHT/
ISSUED AT 215 PM MDT MON OCT 21 2024
IT'S OUT WITH THE FORECAST CHALLENGES OF A CLOSED UPPER LOW
SYSTEM MOVING ACROSS THE AREA AND IN WITH POSSIBLE FREEZING
TEMPERATURES IN SEVERAL OF THE VALLEY LOCATIONS THE NEXT
SEVERAL NIGHTS. UNFORTUNATELY THE BLENDED FORECAST FOR THIS
MORNING WERE WAY TO COLD AND LINGERING CLOUDS KEPT AREAS WELL
ABOVE FREEZING. TONIGHT CONFIDENCE IS STILL ON SHAKY GROUND.
VIOLIN PLOTS AND PROBABILITIES STILL SUGGEST THE BLENDED
GUIDANCE IS RUNNING IN THE 10TH PERCENTILE OR LOWER IN MANY
AREAS TONIGHT. THERE IS ALSO LINGERING MOISTURE BEHIND THIS
SYSTEM WITH A FAIRLY GOOD CLOUD COVER PERSISTING OVER THE
NORTHERN AND CENTRAL CWA LATE THIS AFTERNOON. THE PROBABILITY OF
WIDESPREAD FREEZING TEMPERATURES IN OUR WARNINGS APPEAR TO BE
FAIRLY LOW (LESS THAN 50%) BUT IN THE LOWER ELEVATIONS ALONG OUR
RIVER VALLEYS THIS IS MORE PROBABLE. SO HANDED WATCHES DID GO
AHEAD AND UPGRADE BUT UNDER SOME TREPIDATION. CLEARER SKIES AND
DRIER CONDITIONS WOULD FAVOR COLDER TEMPERATURES TUESDAY MORNING
AND THE 3RD TIME MAY BE THE CHARM FOR MANY AREAS. OTHERWISE
THERE MAY BE SOME PATCHY RIVER VALLEY/BASIN FOG DEVELOP TONIGHT
AS SKIES DO CLEAR...DRIER AIR MOVES IN ALOFT AND THE PBL REMAINS
SATURATED. TEMPERATURES TOMORROW WILL BEGIN A WARMING TREND FOR
THE REMAINDER OF THE WEEK AND PUSH UP TO SEVERAL DEGREES ABOVE
NORMAL IN MANY SNOW FREE AREAS.
LONG TERM /WEDNESDAY THROUGH MONDAY/
ISSUED AT 215 PM MDT MON OCT 21 2024
GENERALIZED RIDGING WILL PERSIST THROUGH THE MAJORITY OF THE LONG
TERM PERIOD, WITH TEMPERATURES RUNNING 5-10 DEGREES ABOVE NORMAL. ON
WEDNESDAY EVENING A SHORTWAVE WILL MOVE INTO THE PACIFIC NORTHWEST
AND QUICKLY TRACK EAST ACROSS THE NORTHERN ROCKIES, POTENTIALLY
CLIPPING NORTHERN PORTIONS OF EASTERN UTAH AND WESTERN COLORADO. A
WEAK COLD FRONT WITH THIS WAVE WILL COOL HIGHS ON THURSDAY, WITH THE
MOST SUBSTANTIAL COOLING OF 5-8 DEGREES ANTICIPATED FOR NORTHWEST
COLORADO AND NORTHEAST UTAH. FOR THE I-70 CORRIDOR AND POINTS SOUTH,
TEMPERATURES WILL BE LARGELY THE SAME OR A DEGREE OR TWO COOLER
COMPARED TO WEDNESDAY. DEPENDING ON HOW MUCH MOISTURE THIS WAVE HAS
WITH IT, A FEW LIGHT SNOW SHOWERS WILL BE POSSIBLE THURSDAY
AFTERNOON OVER THE PARK RANGE, OTHERWISE, CONDITIONS WILL REMAIN DRY
AND QUIET. QUASI-ZONAL FLOW REASSERTS ITSELF EARLY FRIDAY, WITH A
WARMING TREND RETURNING FOR THE REGION. TEMPERATURES WILL REBOUND
ACROSS THE NORTH, WHILE REMAINING FAIRLY CONSISTENT FOR I-70 AND
POINTS SOUTH. A HIGHLY AMPLIFIED RIDGE STRETCHING FROM BAJA
CALIFORNIA NORTHWARD THROUGH THE GREAT BASIN AND INTO NORTHERN
CANADA WILL TAKE CONTROL LATE FRIDAY AND LINGER INTO LATE SATURDAY
NIGHT OR EARLY SUNDAY, MAINTAINING THE WARM AND QUIET PATTERN. A
PACIFIC TROUGH REACHES THE WEST COAST ON SUNDAY, NUDGING THE RIDGE
EAST AND TURNING THE FLOW ALOFT SLIGHTLY SOUTHWESTERLY. BREEZY
CONDITIONS WILL BE POSSIBLE MONDAY WITH STRENGTHENING FLOW AS THE
PRESSURE GRADIENT TIGHTENS AND AN UPPER LEVEL JET NOSES IN OVERHEAD.
ENSEMBLES HAVE BEEN INDICATING A TROUGH DROPPING INTO THE GREAT
BASIN FOR SEVERAL RUNS NOW, AND DETERMINISTIC MODELS ARE GENERALLY
ON BOARD, ASIDE FROM THE EXPECTED DISCREPANCIES IN DETAILS. TO HAVE
SUCH A STRONG SIGNAL AT THIS LEAD TIME MAKES THIS AN EVENT TO KEEP A
VERY CLOSE EYE ON IN THE COMING DAYS. IT'S LOOKING LIKE COOL AND
UNSETTLED WEATHER WILL RETURN TO CLOSE OUT THE MONTH OF OCTOBER AND
KICK OF NOVEMBER.
AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/
ISSUED AT 541 PM MDT MON OCT 21 2024
VFR CONDITIONS ARE FORECAST THROUGH THE TAF PERIOD WITH LIGHT,
TERRAIN-DRIVEN WINDS. TERMINALS THAT STILL HAVE CLOUD COVER WILL
SEE IMPROVEMENT TO MOSTLY CLEAR SKIES BY TOMORROW AFTERNOON.
GJT WATCHES/WARNINGS/ADVISORIES
CO...FREEZE WARNING FROM 10 PM THIS EVENING TO 10 AM MDT TUESDAY
FOR COZ002-005-008-021>023.
UT...NONE.
SHORT TERM...15
LONG TERM...BGB
AVIATION...TGJT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page