135  
FXUS65 KSLC 101006  
AFDSLC  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SALT LAKE CITY UT  
406 AM MDT FRI OCT 10 2025  
   
SYNOPSIS
 
SHOWERS AND THUNDERSTORMS WILL CONTINUE AS TROPICAL  
MOISTURE CONTINUES TO STREAM INTO UTAH, PRODUCING A SIGNIFICANT  
FLASH FLOOD THREAT, ESPECIALLY ACROSS SOUTHERN AND EASTERN UTAH.  
HEAVY RAINFALL WILL REMAIN A THREAT THROUGH AT LEAST SATURDAY, WITH  
A HEIGHTENED SEVERE THUNDERSTORM THREAT ON SATURDAY AFTERNOON AS A  
STRONG COLD FRONT CROSSES THE AREA.  
 

 
   
DISCUSSION
 
 
KEY MESSAGES:  
* TROPICAL MOISTURE WILL PRODUCE A SIGNIFICANT FLASH FLOOD THREAT  
THROUGH SATURDAY, PARTICULARLY ACROSS SOUTHERN AND EASTERN UTAH. A  
SLIGHT (LEVEL 2 OUT OF 4) TO MODERATE RISK (LEVEL 3 OUT OF 4) FOR  
EXCESSIVE RAINFALL MAY RESULT IN FLOODING OF SLOT CANYONS,  
NORMALLY DRY WASHES, RECENT BURN SCARS, AND OTHER FLOOD-PRONE  
LOCATIONS. BACKCOUNTRY ROADS MAY BECOME IMPASSABLE.  
* ON SATURDAY, STRONG TO SEVERE STORMS ARE POSSIBLE IN THE AFTERNOON  
AS A POTENT COLD FRONT SWEEPS THROUGH THE STATE, WITH A MARGINAL  
RISK (LEVEL 1 OUT OF 5) FOR SEVERE THUNDERSTORMS.  
* GUSTY SOUTHWESTERLY WINDS WILL DEVELOP AHEAD OF THIS COLD FRONT ON  
SATURDAY; THE MOST LIKELY GUSTS ARE TO 30-40 MPH ACROSS WESTERN  
VALLEYS, WITH A LOW (10-25%) CHANCE OF REACHING 45 MPH.  
* SNOW LEVELS WILL PLUMMET BEHIND THE COLD FRONT DOWN TO AS LOW AS  
6000FT ACROSS NORTHERN UTAH (7500FT ACROSS SOUTHERN UTAH),  
RESULTING IN MINOR SNOW ACCUMULATIONS IN THE NORTHERN MOUNTAINS.  
 
A CLOSED LOW IS IN PLACE EARLY THIS MORNING OFF THE PACNW COAST  
WHILE WHAT IS NOW TROPICAL STORM PRISCILLA IS NOTED OVER THE CENTRAL  
BAJA COAST. UTAH IS UNDER A SOUTHWESTERLY FLOW DOWNSTREAM OF THE  
PACNW LOW, DRAWING TROPICAL MOISTURE FROM PRISCILLA INTO THE AREA.  
LATEST PWAT ANALYSIS HAS OVER 1-1.2 INCHES ACROSS SOUTHERN UTAH,  
WITH GENERALLY 0.7-0.9 INCHES ACROSS THE NORTH. THIS IS EXPECTED TO  
CONTINUE TO INCREASE THROUGH THE MORNING HOURS, PEAKING AT AROUND  
1.25 INCHES ACROSS FAR SOUTHERN AND SOUTHEAST UTAH AND AROUND 1 INCH  
ELSEWHERE EARLY THIS AFTERNOON. THESE VALUES WOULD BE 250-350% OF  
NORMAL FOR THIS TIME OF YEAR. MEANWHILE, DEWPOINTS ACROSS SOUTHERN  
UTAH HAVE RISEN TO THE 50S AND 60S, WHILE ACROSS NORTHERN UTAH, THEY  
ARE SLIGHTLY DRIER IN THE MID 40S TO MID 50S.  
 
WIDESPREAD RAIN SHOWERS MOVED THROUGH SOUTHERN AND CENTRAL UTAH  
OVERNIGHT, ASSOCIATED WITH A WEAK DISTURBANCE THAT LIFTED THROUGH  
SOUTHERN UTAH. AS THIS FEATURE CONTINUES NORTHEAST, PRECIPITATION  
HAS STARTED TO DECREASE FROM THE SOUTHWEST, WHILE INCREASING ACROSS  
CENTRAL AND NORTHERN UTAH. THIS AREA OF PRECIPITATION WILL THEN  
CONTINUE TO SHIFT INTO NORTH-CENTRAL THROUGH NORTHEAST UTAH AND  
SOUTHWEST WYOMING LATER THIS MORNING. GENERALLY LIGHT TO MODERATE  
RAIN HAS BEEN REPORTED WITH THIS PRECIPITATION, BUT SINCE THIS HAS  
BEEN OCCURRING OVER A LARGE AREA, BRIEF RISES WERE NOTED EARLIER ON  
A FEW RIVER GAGES ACROSS SOUTHERN UTAH.  
 
ANOTHER ROUND OF INTENSIFYING PRECIPITATION IS EXPECTED LATER THIS  
MORNING THROUGH THIS AFTERNOON AND INTO THIS EVENING, AGAIN FOCUSING  
ON SOUTHERN AND EASTERN UTAH, WITH MORE ISOLATED TO SCATTERED  
COVERAGE OF SHOWERS ACROSS THE NORTH AND WEST. RAIN WILL GENERALLY  
REMAIN LIGHT TO MODERATE, BUT OCCASIONAL BURSTS OF HEAVIER RAIN  
(MOST LIKELY FROM MID-AFTERNOON THROUGH THIS EVENING) WILL LEAD TO  
AN INCREASED THREAT OF FLASH FLOODING, ESPECIALLY NEAR RECENT BURN  
SCARS, SLOT CANYONS, NORMALLY DRY WASHES, AND OTHER PRONE AREAS.  
SHOWERS WILL CONTINUE TONIGHT AND INTO SATURDAY MORNING. THE WEATHER  
PREDICTION CENTER NOW HAS A MODERATE RISK IN ITS EXCESSIVE RAINFALL  
OUTLOOK ACROSS SOUTHWEST THROUGH SOUTH-CENTRAL UTAH WITHIN A LARGER  
SLIGHT RISK AREA FOR THE PERIOD 12Z TODAY THROUGH 12Z SATURDAY. ALL  
THAT SAID, THERE IS STILL A FAIR AMOUNT OF SPREAD IN PRECIPITATION  
AMOUNTS, AS THE NBM 25TH PERCENTILE AMOUNTS OVER THE NEXT 24 HOURS  
RANGE FROM AROUND 0.25 INCHES ACROSS THE SOUTHEAST TO 0.45 INCHES  
ACROSS THE SOUTHWEST, WHILE THE 75TH PERCENTILE AMOUNTS RANGE FROM  
AROUND 0.8 INCHES ACROSS THE SOUTHEAST TO 1.5 INCHES ACROSS THE  
SOUTHWEST.  
 
BY SATURDAY AFTERNOON, THE UPSTREAM LOW WILL APPROACH UTAH AS AN  
OPEN-WAVE TROUGH, AND STRONGER SOUTHWEST FLOW WILL AID IN BRINGING  
INCREASED SHEAR TO THE AREA. THE HREF ENSEMBLE MEAN SHOWS A SIZABLE  
AREA OF 500-1000+ J/KG OF SBCAPE OVER UTAH, ALONG WITH 25-50+KT OF  
SFC-500MB SHEAR. WITH MOISTURE REMAINING IN PLACE AND SHOWERS  
CONTINUING, THIS WILL BRING THE POTENTIAL FOR STRONG TO SEVERE  
STORMS WITH A POTENTIAL FOR STRONG WINDS AND HAIL. THIS WILL  
CONTINUE AHEAD OF AND ALONG A STRONG COLD FRONT WHICH WILL CROSS  
NORTHWEST UTAH LATE SATURDAY AFTERNOON THROUGH SATURDAY EVENING, AND  
THROUGH THE REST OF THE FORECAST AREA SATURDAY NIGHT INTO SUNDAY  
MORNING. THE STORM PREDICTION CENTER HAS A MARGINAL RISK FOR SEVERE  
WEATHER FOR THE VAST MAJORITY OF THE FORECAST AREA FOR SATURDAY.  
ADDITIONALLY, NORTHERN UTAH WILL LIKELY SEE ITS BEST WINDOW FOR  
SIGNIFICANT PRECIPITATION ON SATURDAY, ESPECIALLY AROUND THE TIME OF  
THE FRONTAL PASSAGE. THE NBM HAS A 40-75% CHANCE OF 1 INCH OR  
GREATER ALONG THE WASATCH FRONT BETWEEN SATURDAY MORNING AND SUNDAY  
MORNING.  
 
AS THE AIRMASS GRADUALLY DRIES BEHIND THE COLD FRONT SATURDAY NIGHT  
THROUGH SUNDAY, MUCH COOLER AIR WILL SETTLE INTO THE AREA. AS SNOW  
LEVELS LOWER, EXPECT SOME ACCUMULATING SNOW FOR THE HIGHER  
ELEVATIONS (GENERALLY 6000-6500FT OR HIGHER) OF NORTHERN AND CENTRAL  
UTAH. BECAUSE THE PRECIPITATION WILL BE WINDING DOWN AS THE COLD AIR  
MOVES IN, SNOW ACCUMULATIONS ARE NOT EXPECTED TO BE SIGNIFICANT(55%  
CHANCE OF GREATER THAN 4 INCHES IN THE UPPER COTTONWOODS BUT  
GENERALLY LESS THAN 35% CHANCE ELSEWHERE).  
 
A BREAK IN THE WEATHER IS EXPECTED LATE SUNDAY THROUGH MONDAY, BUT  
THIS BREAK WILL BE SHORT-LIVED AS THE NEXT STORM SYSTEM WILL AMPLIFY  
ALONG THE WEST COAST ON MONDAY BEFORE MOVING INLAND TUESDAY INTO  
WEDNESDAY. THIS WILL BRING INCREASING SOUTHERLY FLOW ALONG WITH SOME  
MOISTURE WHICH, WHEN AIDED BY UPPER DIFFLUENCE AHEAD OF THE STORM,  
WILL BRING A PERIOD OF UNSETTLED WEATHER BACK TO THE AREA.  
 

 
   
AVIATION...KSLC
 
AN ACTIVE TAF PERIOD IS IN STORE FOR KSLC WITH  
MOUNTAIN OBSCURATIONS LIKELY THROUGHOUT THE MAJORITY OF THE DAY,  
OCCASIONAL MVFR VISIBILITIES, AND PREVAILING SHOWERS WITH OCCASIONAL  
THUNDERSTORMS NEAR THE TERMINAL. THROUGH THE PERIOD, WINDS WILL  
REMAIN OUT OF THE SOUTH AT AROUND 10KTS. THUNDERSTORM CHANCES NEAR  
THE TERMINAL APPEAR MOST LIKELY FROM 10-14Z AND 21-01Z WITH ERRATIC  
WINDS AND GUSTS TO AROUND 30KTS.  
   
REST OF UTAH AND SOUTHWEST WYOMING
 
AN ACTIVE DAY OF WEATHER IS  
EXPECTED ACROSS ALL OF OUR SITES WITH AN EXTENDED PERIOD OF MOUNTAIN  
OBSCURATIONS, PREVAILING RAINFALL OCCASIONALLY RESULTING IN MVFR  
CIGS, AND AFTERNOON THUNDERSTORMS. WINDS WILL GENERALLY REMAIN OUT  
OF THE SOUTH AROUND 10KTS WITH ERRATIC GUSTS IN THUNDERSTORMS TO  
AROUND 30KTS.  
 

 
   
FIRE WEATHER
 
ABUNDANT MOISTURE FROM A TROPICAL SYSTEM CONTINUES  
TO SPREAD INTO UTAH TODAY, RESULTING IN INCREASED HUMIDITIES AND  
WIDESPREAD SHOWERS WITH ISOLATED TO SCATTERED THUNDERSTORMS ACROSS A  
LARGE PORTION OF THE AREA. WETTING RAIN WILL BE LIKELY ESPECIALLY  
ACROSS SOUTHERN AND EASTERN UTAH TODAY. FAR NORTHWEST UTAH WILL SEE  
MORE ISOLATED SHOWERS AND THUNDERSTORMS TODAY WITH MUCH LOWER  
POTENTIAL FOR WETTING RAIN. SHOWERS WILL CONTINUE OVERNIGHT AND INTO  
SATURDAY. AS SOUTHWEST FLOW STRENGTHENS FOR SATURDAY AFTERNOON AHEAD  
OF AN APPROACHING COLD FRONT, SOME THUNDERSTORMS MAY BE STRONG AND  
PRODUCE GUSTY WINDS AND HAIL. THE COLD FRONT IS EXPECTED TO CROSS  
NORTHWEST UTAH LATE SATURDAY AFTERNOON THROUGH SATURDAY EVENING, AND  
THE REST OF THE AREA SATURDAY NIGHT INTO SUNDAY MORNING. FAIRLY  
WIDESPREAD SHOWERS WILL CONTINUE ALONG THE COLD FRONT BEFORE  
GRADUALLY WINDING DOWN SATURDAY NIGHT AND SUNDAY MORNING. NORTHERN  
UTAH WILL LIKELY SEE WETTING RAIN NEAR THE COLD FRONT SATURDAY  
EVENING. HIGHER ELEVATIONS, GENERALLY ABOVE 6500 FEET, ARE EXPECTED  
TO SEE ACCUMULATING SNOW SATURDAY NIGHT THROUGH SUNDAY MORNING AS A  
MUCH COOLER AIRMASS SETTLES INTO THE AREA BEHIND THE COLD FRONT.  
THEREAFTER, A GENERAL WARMING AND DRYING TREND CAN BE EXPECTED LATE  
SUNDAY THROUGH MONDAY. BY THE MIDDLE OF NEXT WEEK, ANOTHER STORM  
SYSTEM WILL APPROACH UTAH, BRINGING ANOTHER PERIOD OF UNSETTLED  
WEATHER TO THE AREA.  
 

 
   
SLC WATCHES/WARNINGS/ADVISORIES
 
 
UT...FLOOD WATCH THROUGH SATURDAY EVENING FOR UTZ113-117-120>131.  
 
WY...NONE.  

 
 

 
 
CHENG/WORSTER  
 
FOR MORE INFORMATION FROM NOAA'S NATIONAL WEATHER SERVICE VISIT...  
HTTP://WEATHER.GOV/SALTLAKECITY  
 
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