681
FXUS65 KSLC 192308
AFDSLC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
408 PM MST WED FEB 19 2025
SYNOPSIS
WIDESPREAD PRECIPITATION WILL MOVE INTO THE NORTHERN
HALF OF THE AREA OVERNIGHT WITH MOUNTAIN SNOW AND VALLEY RAIN
QUICKLY TRANSITIONING TO SNOW. EXPECT IMPACTS TO THE THURSDAY
MORNING COMMUTE. THE REMAINDER OF THE WEEK WILL CONSIST OF DRY
CONDITIONS WITH WARMING TEMPERATURES.
SHORT TERM (THROUGH 12Z/5AM FRIDAY)
* HIGH CONFIDENCE IN ACCUMULATING MOUNTAIN SNOW FOR THE NORTHERN
AND CENTRAL MOUNTAINS.
* HIGH CONFIDENCE IN SNOW IMPACTING THE THURSDAY MORNING COMMUTE
FOR PARTS OF THE WASATCH FRONT AND TOOELE VALLEY.
* MEDIUM CONFIDENCE ON EXACTLY WHEN RAIN TRANSITIONS TO SNOW AND
WHERE THE HIGHEST SNOW TOTALS WILL OCCUR.
MOIST SOUTHWEST FLOW IS ADVECTING MOISTURE INTO THE REGION,
RESULTING IN SOME LIGHT SNOW OVER THE MOUNTAINS OF CENTRAL AND
NORTHERN UTAH THIS AFTERNOON. THIS ACTIVITY WILL SHIFT EAST
THROUGHOUT THE EVENING BEFORE A MORE POTENT TROUGH MOVES INTO THE
AREA OVERNIGHT WITH IMPACTS TO THE THURSDAY MORNING COMMUTE.
A MOIST TROUGH CURRENTLY CENTERED OVER CENTRAL OREGON WILL
CONTINUE TO TREK TO THE EAST/SOUTHEAST WITH AN ARRIVAL OF THE
INITIAL BAROCLINIC ZONE AROUND MIDNIGHT. PRECIPITATION WILL
QUICKLY FILL IN ALONG AND BEHIND THIS FRONTAL BOUNDARY WITH
SOUTHWESTERLY FLOW TRANSITIONING TO WESTERLY/NORTHWESTERLY FLOW.
MODEL SOUNDINGS INDICATE PRECIPITATION STARTING AS RAIN BEFORE
THERMODYNAMIC PROFILES QUICKLY COOL WITH A TRANSITION TO SNOW
CLOSE TO VALLEY FLOORS. THERE IS ~25% CHANCE THAT THE LOWEST
VALLEY FLOORS STRUGGLE TO TRANSITION OVER WHICH COULD IMPACT THE
SNOW TOTALS FOR AREAS THAT STAY A RAIN/SNOW MIX.
LOOKING FURTHER INTO THE SOUNDING PROFILES, THERE EXISTS SEVERAL
PARAMETERS THAT WOULD SUGGEST HIGHER SNOW RATES ACROSS PORTIONS
OF THE WASATCH FRONT. MOISTURE WILL BE ABUNDANT WITH THIS STORM
WITH MOST OF THE PROFILE NEARLY SATURATED UP TO ~400 MB THAT WILL
HELP TO PRODUCE WIDESPREAD PRECIPITATION. THIS MOIST PROFILE WILL
PAIR WITH A DEEP OMEGA LAYER AND STEEPENING LAPSE RATES THROUGH
THE EARLY MORNING HOURS. ADDITIONALLY, FLOW ALOFT WILL BE
RELATIVELY LIGHT AND UNIDIRECTIONAL WHICH WILL HELP TO LIMIT
DENDRITIC SNOW COLLISION PROCESSES LEADING TO LARGER SNOWFLAKES
AND MORE EFFICIENT ACCUMULATION. THIS RELATIVELY LIGHT FLOW WILL
PROMOTE HIGHER SNOW ACROSS THE BENCHES AND MID MOUNTAIN AREAS WITH
SOME OF THE HEAVIEST SNOW STRUGGLING TO MAKE IT TO RIDGETOPS AND
OVER THE TERRAIN INTO THE WASATCH BACK.
THE ONE UNCERTAINTY WITH THE FLOW ALOFT WILL BE THE DIRECTION.
GUIDANCE IS SPLIT BETWEEN MORE OF A WESTERLY FLOW THAT WOULD FAVOR
HIGHER SNOW TOTALS FROM BOX ELDER TO DAVIS COUNTY, OR MORE OF A
NORTHWESTERLY FLOW THAT WOULD FAVOR HIGHER SNOW TOTALS ACROSS
CACHE VALLEY AND SALT LAKE COUNTY.
THE TIME OF HIGHEST SNOWFALL RATES WILL BE BETWEEN 4AM-10AM WITH
AN INCH OR TWO OF SNOW HAVING ALREADY FALLEN BY THE BEGINNING OF
THE MORNING COMMUTE. TEMPERATURES WILL BE NEAR FREEZING SO SNOW
WILL HAVE A HARD TIME ADHERING TO SURFACES INITIALLY, BUT HIGH
RATES SHOULD BE ABLE TO OVERCOME THIS. SNOW WILL GRADUALLY
DIMINISH THROUGHOUT THE DAY ON THURSDAY WITH AREAS FAVORED IN
WESTERLY OR NORTHWESTERLY FLOW (WHICHEVER PREVAILS) CONTINUING
WITH SNOW THROUGH THE AFTERNOON. SNOW WILL TAPER OFF BY THE
EVENING AND OVERNIGHT HOURS ACROSS THE MOUNTAINS.
ALL IN ALL, CENTRAL AND NORTHERN MOUNTAINS CAN EXPECT BETWEEN 5
TO 10 INCHES WITH LOCALLY HIGHER AMOUNTS UP TO 15 INCHES IN THE
COTTONWOODS. VALLEYS OF NORTHERN UTAH WILL SEE 1 TO 4 INCHES WITH
LOCALLY HIGHER AMOUNTS CLOSER TO 6 INCHES ALONG THE EAST BENCHES.
LIGHT ACCUMULATIONS OF 1 TO 2 INCHES WILL BE POSSIBLE ACROSS THE
VALLEYS OF CENTRAL UTAH UP THROUGH UTAH COUNTY.
LONG TERM (AFTER 12Z/5AM FRIDAY)
GENERAL MODEL CONSENSUS BRINGS
LONGWAVE RIDGING OVER THE WESTERN US FOLLOWING THE DEPARTURE OF
THE RECENT SYSTEM THIS FRIDAY. THIS RIDGE WILL REMAIN IN PLACE FOR
QUITE SOME TIME, AT LEAST THROUGH MIDWEEK WITH AROUND 30% OF
ENSEMBLES KEEPING US UNDER A RIDGE THROUGH FRIDAY, BRINGING
SEASONABLY WARM TEMPERATURES TO UTAH AND SOUTHWEST WYOMING WITH
BELOW AVERAGE PRECIPITATION. POPS THROUGH THE EXTENDED FORECAST
REMAIN QUITE LIMITED, AROUND 10-20%, AS A COUPLE SOLUTIONS FLATTEN
THE RIDGE AXIS ALLOWING SOME MOISTURE TO SLIP AROUND IT INTO
NORTHERN UTAH WHICH COULD SPARK A FEW SHOWERS ACROSS THE NORTHERN
MOUNTAINS SUNDAY THROUGH MONDAY. REGARDLESS, THIS SOLUTIONS
APPEARS TO BE SOMEWHAT UNLIKELY AT THIS TIME GIVEN THAT ~80% OF
ALL OTHER ENSEMBLE MEMBERS KEEP US DRY. THE CLIMATE PREDICTION
CENTER (CPC) HAS OUR FORECAST AREA OUTLINED FOR ABOVE AVERAGE
TEMPERATURES AND NEAR-NORMAL PRECIPITATION CHANCES FOR THE NEXT
8-14 DAYS.
REGARDING TEMPERATURES, THE EXTREME FORECAST INDEX (EFI) HAS A
PRETTY NOTABLE SIGNAL ACROSS THE ENTIRE FORECAST AREA FROM MONDAY
THROUGH THURSDAY. PRONOUNCED MID-LEVEL HEIGHT RISES THROUGH THE
START OF THE WEEK WILL YIELD SEASONABLY WARM TEMPERATURES THROUGHOUT
THE WHOLE STATE AND PARTICULARLY SOUTHERN UTAH WHERE TEMPERATURES
COULD PERHAPS REACH AS HIGH AS 80 DEGREES NEAR ST. GEORGE.
ADDITIONALLY, THE SLC AREA WILL LIKELY SEE TEMPERATURES BREAK INTO
THE LOW 50S POSSIBLY AS EARLY AS SUNDAY, WARMING INTO THE MID 50S
COME MONDAY.
AS WE APPROACH THE TAIL END OF FEBRUARY, THERE IS A SIGNAL AMONGST
ENSEMBLE MEMBERS INDICATING THE RIDGE BREAKING DOWN WITH ANOTHER
TROUGH MOVING IN, THOUGH IT IS QUITE FAR OUT IN THE FORECAST AND
RELATIVELY UNLIKELY. HOWEVER, THE CPC DOES HAVE NORTHERN UTAH
OUTLINED FOR SLIGHTLY ABOVE NORMAL IN THEIR WEEKS 3-4 PRECIPITATION
OUTLOOK, SO NOT ALL HOPE IS LOST. REGARDLESS, BE SURE TO GET OUTSIDE
AND ENJOY THOSE PLEASANTLY WARM TEMPERATURES!
AVIATION...KSLC
CONDITIONS ARE EXPECTED TO REMAIN DRY, WITH
SOUTHERLY WINDS AND OVERCAST SKIES PREVAILING THIS EVENING. A BAND
OF HEAVY PRECIPITATION IS EXPECTED TO ACCOMPANY A COLD FRONTAL
PASSAGE ROUGHLY AFTER 06Z THURSDAY. HIGH-RES GUIDANCE SUGGESTS
PRECIPITATION MAY START AS RAIN, BUT QUICKLY TRANSITION TO SNOW AS
HIGH PRECIPITATION INTENSITY DRAGS SNOW LEVELS BELOW VALLEY LEVELS.
THERE IS A 30% CHANCE FOR SNOW RATES TO REACH 1"/HR AT TIMES DURING
THE 06-10Z TIMEFRAME, WHICH MAY YIELD PERIODS OF IFR CONDITIONS.
LOWER CONFIDENCE IN WIND DIRECTION DURING AND FOLLOWING
PRECIPITATION DURING THIS PERIOD. PRECIPITATION BECOMES MORE SHOWERY
AND THERE IS A STRONGER SIGNAL FOR WINDS TO SHIFT NORTHWESTERLY
FOLLOWING THE HEAVY BAND AROUND ROUGHLY 12Z. SHOWERS MAY TRANSITION
TO A RAIN/SNOW MIX BY THURSDAY AFTERNOON. OTHERWISE, SHOWERS ARE
EXPECTED TO TAPER OFF THURSDAY EVENING AS DRIER AIR MOVES INTO THE
REGION.
REST OF UTAH AND SOUTHWEST WYOMING
CONDITIONS REMAIN MOSTLY DRY
THROUGH THIS EVENING, EXCEPT FOR LIGHT SHOWERS ACCOMPANYING A WARM
FRONT OVER FAR NORTHERN UTAH AND SOUTHWEST WYOMING. SHOWERS
ASSOCIATED WITH THIS FEATURE ARE EXPECTED TO TAPER AFTER 00Z
THURSDAY, WITH A BRIEF LULL EXPECTED BEFORE A BAND OF HEAVY
PRECIPITATION ACCOMPANYING A COLD FRONT PASSAGE MOVES INTO
NORTHERN/CENTRAL UTAH AND SOUTHWEST WYOMING LATE THIS EVENING AND
OVERNIGHT. HEAVY SNOW SHOWERS UNDER THIS BAND MAY BRING IFR CIGS/VIS
TO MANY AREA TERMINALS. SNOW SHOWERS THEN BECOME INCREASINGLY TIED
TO TERRAIN BY LATE THURSDAY AFTERNOON BEFORE GRADUALLY DIMINISHING
IN THE EVENING. SOUTHERN UTAH TERMINALS TO REMAIN DRY WITH VFR
CONDITIONS PREVAILING THROUGH THE PERIOD.
SLC WATCHES/WARNINGS/ADVISORIES
UT...WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 5 PM MST
THURSDAY FOR UTZ102>105-107.
WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 11 PM MST
THURSDAY FOR UTZ110>113-117.
WY...WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 11 PM MST
THURSDAY FOR WYZ021.
SHORT TERM...MAHAN
LONG TERM...WORSTER
AVIATION...WHITLAM
FOR MORE INFORMATION FROM NOAA'S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page