510
FXUS65 KSLC 192314
AFDSLC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
414 PM MST FRI DEC 19 2025
KEY MESSAGES
- A PERIOD OF MORE SIGNIFICANT PRECIPITATION AND STRONG WINDS ARE
EXPECTED ACROSS NORTHERN UTAH THIS EVENING, STALLING ALONG AN
AXIS FROM PROVO TO EVANSTON, BEFORE PROGRESSING SOUTHWARD
TOWARDS THE CENTRAL MOUNTAINS OVERNIGHT. SNOW LEVELS REMAIN HIGH
AT 7 KFT+, FINALLY FALLING EARLY MORNING SATURDAY.
- ANOTHER IMPULSE OF MOISTURE WILL PASS THROUGH NORTHERN UTAH FROM
SUNDAY THROUGH TUESDAY, BRINGING ANOTHER ROUND OF HIGH ELEVATION
SNOW AND VALLEY RAIN.
- AFTER A RELATIVE LULL IN ACTIVE WEATHER EARLY NEXT WEEK, ANOTHER
PACIFIC STORM WILL BRING ANOTHER ROUND OF VALLEY RAIN AND
MOUNTAIN SNOW CHRISTMAS EVE AND CHRISTMAS DAY.
DISCUSSION
CURRENT SATELLITE AND RADAR POSITION A NARROWING
BAND OF MOISTURE BECOMING MORE CONCENTRATED BEHIND A NOTABLE UPPER
LEVEL BOUNDARY STRETCHING FROM WEST-CENTRAL NEVADA TO NORTHEASTERN
WYOMING SLOWING PROGRESSING SOUTHWARD. AHEAD OF THIS FEATURE
APPEARS TO BE A WEAK SECONDARY LOW THAT WILL BRING ORGANIZED
PRECIPITATION AND GUSTIER WINDS TO MUCH OF NORTHERN UTAH AND
SOUTHWEST WYOMING THIS EVENING, PROGRESSING SOUTH THROUGH THE UTAH
VALLEY OVERNIGHT, SPREADING INTO THE CENTRAL UTAH MOUNTAINS BY
MORNING. SNOW LEVELS REMAIN REMARKABLY HIGH FOR MUCH OF THIS
EVENT, HANGING AROUND 7500-8500 FT UNTIL H7 TEMPS CRASH BETWEEN
MIDNIGHT AND 3AM WITH THE SOUTHWARD PROGRESSION OF THE UPPER
LEVEL FRONT. FOR MOST AREAS, THE PRECIPITATION IS EXPECTED TO
QUICKLY TAPER OFF WITH THE ARRIVAL OF COLDER AND DRIER AIR,
LIMITING OVERALL SNOW ACCUMULATIONS. AREAS LIKE DANIELS SUMMIT, A
FEW HIGH ELEVATION PORTIONS OF I-70 AND I-15 IN CENTRAL UTAH, AND
THE UPPER REACHES OF THE COTTONWOOD CANYONS MAY SEE SOME MINIMAL
ACCUMULATING SNOW OVERNIGHT.
THE NEXT IMPACTFUL PERIOD BEGINS EARLY SUNDAY AS ANOTHER PLUME OF
MOISTURE AND SUPPORTIVE UPPER LEVEL DYNAMICS ARRIVES, THOUGH
THROUGH A MUCH LESS IDEAL WSW PATHWAY. AS THE LANDFALLING
ATMOSPHERIC RIVER SAGS SOUTHWARD, MEMBERS ACROSS THE ENSEMBLE
SUITE ARE IN GOOD AGREEMENT IN CUTTING OFF THE PLUME MAKING IT
INTO THE FORECAST AREA, LIMITING THE IMPACTS LARGELY TO NORTHERN
UTAH AND SW WYOMING. YET AGAIN UNSEASONABLY WARM TEMPS WILL
ACCOMPANY THIS SYSTEM, DRIVING EVEN THE MOST OPTIMISTIC SNOW LEVEL
FORECASTS ABOVE 7500 FT AGAIN, AS HIGH AS 9KFT IN PORTIONS OF THE
NORTHERN WASATCH.
AFTER A BRIEF BREAK TUESDAY, ANOTHER STORM SYSTEM TEES UP FOR THE
24TH-25TH WITH ABOUT 80% OF THE GLOBAL ENSEMBLE MEMBERSHIP
SUPPORTING AN OPEN PROGRESSIVE WAVE AMPLIFYING INTO THE
INTERMOUNTAIN WEST. THIS SCENARIO WOULD SUPPORT, FINALLY, THE
SOUTHWARD PUSH OF COLDER H7 TEMPS AND MORE SEASONALLY APPROPRIATE
SNOW LEVELS FOR NORTHERN UTAH. HOWEVER, AS THE MOISTURE SOURCE IS
ONCE AGAIN A WARM LANDFALLING ATMOSPHERIC RIVER, THE ARRIVAL COLD
AIR FROM THE NORTH WILL BUTT UP AGAINST A WARM AND MOIST AIRMASS
ARRIVING FROM THE SW VIA FAR SOUTHERN CALIFORNIA. THE ALTERNATIVE
SCENARIO SUPPORTED IN 20% OF THE MEMBERSHIP HOLD BACK THE UPPER
LEVEL TROUGH AT THE CALIFORNIA COAST, CUTTING OFF, AND STALLING
FOR A DAY OR TWO BEFORE FINALLY PROGRESSING EASTWARD. THIS WOULD
PRESENT A DRIER, WARMER ALTERNATIVE OUTCOME FOR THE HOLIDAY.
AVIATION...KSLC
A COLD FRONT WILL BRING A BRIEF TRANSITION FROM
SOUTH WINDS TO NORTH WINDS AROUND 23-00Z, LASTING UNTIL AROUND 01-
03Z WHEN LIGHTER, SOUTHEASTERLY WINDS WILL PERSIST THROUGH MUCH OF
THE OVERNIGHT HOURS. RAIN WILL ALSO ACCOMPANY THIS COLD FRONT, WITH
MOUNTAIN OBSCURATION AND BRIEF PERIODS OF MVFR VIS LASTING THROUGH
ROUGHLY 04-05Z. THERE IS A CHANCE THAT THIS PRECIPITATION HOLDS ON
LONGER IF THE FRONT STALLS SLIGHTLY FURTHER NORTH.
REST OF UTAH AND SOUTHWEST WYOMING...GUSTY WESTERLY TO SOUTHWESTERLY
WINDS WILL PERSIST THROUGH THE EARLY EVENING ACROSS MANY SITES,
PARTICULARLY THOSE AT HIGHER ELEVATIONS. AT KEVW IN PARTICULAR,
WINDS WILL FINALLY BEGIN TO DROP OFF AFTER 00-02Z WHEN A COLD FRONT
BRINGS RAIN/SNOW AND SLIGHTLY LOWER WINDS AROUND 30-40KTS, STILL OUT
OF THE WEST. THIS COLD FRONT WILL BRING MOSTLY VALLEY RAIN, BECOMING
MORE SHOWERY AFTER ROUGHLY 08Z. THERE IS SOME UNCERTAINTY WITH IF
THIS COLD FRONT STALLS OVER PARTS OF NORTHERN UTAH, WHICH WOULD
PROLONG RAINFALL, MOUNTAIN OBSCURATION, AND PERIODIC MVFR VIS.
SLC WATCHES/WARNINGS/ADVISORIES
UT...WIND ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR UTZ110.
WINTER WEATHER ADVISORY UNTIL 5 PM MST SATURDAY FOR UTZ112.
WY...HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT FOR WYZ021.
WESSLER/CUNNINGHAM
FOR MORE INFORMATION FROM NOAA'S NATIONAL WEATHER SERVICE
VISIT... HTTP://WEATHER.GOV/SALTLAKECITY
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page