103
FXUS65 KRIW 152259
AFDRIW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
359 PM MST SUN DEC 15 2024
KEY MESSAGES
- SNOW AND WIND CONTINUES TODAY, WITH LESSENING IMPACTS THROUGH
THE AFTERNOON AND EVENING.
- ANOTHER SYSTEM MONDAY AND TUESDAY BRINGS GUSTY WINDS OR THE
WIND CORRIDOR AND WESTERN WYOMING SNOW.
- WARM AND DRY THE SECOND HALF THE WEEK.
DISCUSSION
ISSUED AT 1055 AM MST SUN DEC 15 2024
COMING IN THIS MORNING, SNOW AMOUNTS LOOKED TO BE ON TRACK AS OF
ABOUT 5AM, WITH LARGELY 8 TO 12 INCHES OVER THE WESTERN MOUNTAINS.
HOWEVER, SNOW RATES FELL A BIT MORE THAN EXPECTED OVER THE WESTERN
MOUNTAINS DURING THE MORNING, LIMITING SOME ACCUMULATIONS. AS A
RESULT, WESTERN MOUNTAIN TOTALS MAY BE SLIGHTLY LESS THAN
FORECASTED. MODELS DID DO A GOOD JOB INDICATING A PUSH OF HEAVIER
SNOW MID-MORNING THOUGH, WHICH SHOULD BRING MUCH OF THE REMAINING
SNOW AMOUNTS FOR THIS STORM. SNOW RATES WILL SLOWLY DECREASE THIS
AFTERNOON, ENDING THIS EVENING. SNOW OVER THE BIGHORN MOUNTAINS END
BY ABOUT MIDNIGHT.
FOR LOWER ELEVATIONS OUTSIDE THE WESTERN VALLEYS, LITTLE TO NOTHING
EXPECTED TODAY. A POSSIBLE SHOWER MAY BRING A FEW MOMENTS OF SNOW,
BUT A MAJORITY OF PEOPLE SEE NOTHING. THE CASPER AREA, AS WELL AS
JOHNSON COUNTY, MAY BE THE EXCEPTION AS A COLD FRONT MOVES THROUGH
THIS EVENING. SOME SNOW (OR RAIN/SNOW MIX GIVEN TEMPERATURES) IS
POSSIBLE BETWEEN ABOUT 4PM AND MIDNIGHT. WITH TEMPERATURES
RELATIVELY QUICKLY DROPPING FROM THE 40S TO 20S IN THAT TIMEFRAME,
THERE COULD BE SOME ICY CONDITIONS, ESPECIALLY ON OVERPASSES AND
BRIDGES, IF PRECIPITATION DOES FALL.
THE OTHER WEATHER ELEMENT TODAY IS WIND. SYNOPTIC DRIVEN WINDS WILL
CONTINUE THROUGH THE AFTERNOON AND EARLY EVENING, WITH WIDESPREAD
GUSTS 20 TO 30 MPH. STRONGER WINDS ARE ACROSS THE WIND CORRIDOR. AS
THE FRONT PASSES THIS EVENING, A STRONG NORTH WIND MOVES THROUGH
JOHNSON COUNTY. GIVEN THIS FAVORED FLOW, BUFFALO IS EXPECTED SEE 30
TO 40 MPH WINDS. WITH THE INITIAL PASS, GUSTS AROUND 45 MPH ARE
EXPECTED. THERE IS ABOUT A 20 PERCENT CHANCE FOR WINDS 50 TO 55 MPH.
GUSTY WINDS REMAIN FOR THE WIND CORRIDOR AND THE MOUNTAINS OVERNIGHT
AND THROUGH THE DAY MONDAY.
A QUICK TURN AROUND AFTER TODAY'S STORM MOVES OUT AND OTHER SYSTEM
IMPACTS THE AREA MONDAY AND TUESDAY. MAIN IMPACTS ARE ONCE AGAIN TO
THE WESTERN MOUNTAINS, WHERE AN ADDITIONAL 8 TO 12 INCHES ARE
POSSIBLE FOR THE TETONS. THE NORTHERN SALT/WYOMING RANGES AND THE
GROS VENTRES ARE MORE IN THE 6 TO 10 RANGE. GIVEN CURRENT WINTER
HIGHLIGHTS, WILL NOT BE ISSUING ANY PRODUCTS WITH THIS FORECAST
PACKAGE AND WILL ALLOW NIGHT SHIFT TO REEVALUATE SNOW AMOUNTS.
THE LAST FLAKES SHOULD FALL TUESDAY NIGHT, LEAVING A DRY WEDNESDAY
ACROSS THE AREA (OUTSIDE MAYBE A FEW LINGERING LIGHT SNOW SHOWERS
OVER THE TETONS THROUGH WEDNESDAY MORNING). RIDGING WILL KEEP ABOVE
NORMAL TEMPERATURES AND DRY CONDITIONS ACROSS THE AREA THROUGH THE
SECOND HALF OF THE WEEK, A SIMILAR PATTERN TO WHAT MUCH OF THIS
SEASON HAS SEEN SO FAR. CONDITIONS LOOK WARM AND DRY THROUGH
DECEMBER 22ND. LONG RANGE GUIDANCE IS HINTING AT A SYSTEM THE 23RD,
BUT VERY LOW CONFIDENCE THIS FAR OUT.
AVIATION /00Z TAFS THROUGH 00Z TUESDAY/
ISSUED AT 359 PM MST SUN DEC 15 2024
WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS TERMINALS.
CONDITIONS ARE EXPECTED TO CONTINUE TO IMPROVE AT TERMINALS AS
TODAY'S SYSTEM DEPARTS, WITH VFR CONDITIONS PREVAILING AFTER 00Z.
WIND WILL DECREASE THROUGH THE EVENING. THERE IS SOME INDICATION FOR
FOG AT KBPI OVERNIGHT, BUT CONFIDENCE IS NOT HIGH ON THIS AND WILL
JUST INCLUDE A LOW SCATTERED DECK FOR NOW. THE NEXT SYSTEM WILL
FOLLOW QUICKLY, MOVING INTO WESTERN WYOMING AFTER 12Z. MVFR
CONDITIONS ARE LIKELY AT KJAC AFTER 18Z. WHILE CEILINGS WILL LOWER
AT KBPI AND KPNA DURING THE AFTERNOON, SNOW IMPACTS ARE LARGELY
EXPECTED TO HOLD OFF UNTIL AFTER 00Z TUESDAY.
EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL TERMINALS.
THE GUSTY WIND SEEN ACROSS TERMINALS THIS AFTERNOON WILL DECREASE
OVER THE NEXT FEW HOURS. KCPR WILL STILL HOLD ON TO A BREEZY WIND
THROUGH THE NIGHT, GUSTING OVER 20 KNOTS. ADDITIONALLY, THERE WILL
BE A BRIEF WINDOW FOR A SHOWER AT KCPR THROUGH 03Z, WHICH COULD
RESULT IN LOWERED CEILINGS FOR A TIME. OTHERWISE, VFR CONDITIONS ARE
EXPECTED THROUGH THE PERIOD, WITH WIND AGAIN INCREASING AT KCPR
AFTER 18Z MONDAY.
PLEASE SEE THE AVIATION WEATHER CENTER AND/OR CWSU ZDV AND ZLC FOR
THE LATEST INFORMATION ON ICING, AND TURBULENCE FORECASTS.
RIW WATCHES/WARNINGS/ADVISORIES
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR
WYZ001-008-013.
WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON FOR WYZ012-
014-024.
HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON FOR WYZ020.
DISCUSSION...WITTMANN
AVIATION...MYERS
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