460  
FXUS65 KSLC 191011  
AFDSLC  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SALT LAKE CITY UT  
411 AM MDT TUE MAR 19 2019  
   
SYNOPSIS
 
 
THE NEXT STORM SYSTEM WILL ARRIVE MIDWEEK, WITH IMPACTS PRIMARILY  
ACROSS THE SOUTHERN AND CENTRAL PORTIONS OF THE FORECAST AREA.  
ANOTHER STORM SYSTEM WILL FOLLOW BY LATE THIS WEEKEND.  
 

 
   
SHORT TERM (THROUGH 00Z SATURDAY)
 
 
SEVERAL DISTURBANCES WILL COMBINE TO OUR WEST TODAY AND TONIGHT,  
WITH A SPRING STORM EVENTUALLY EVOLVING. ON APPROACH TODAY AND  
TONIGHT, A BUILDING NORTHEASTERLY PRESSURE GRADIENT WILL COMBINE  
WITH PRESSURE FALLS TO THE WEST TO SUPPORT THE DEVELOPMENT OF  
EAST-NORTHEAST FLOW ACROSS THE STATE. WINDS MAY BE LOCALLY GUSTY  
ALONG THE WASATCH FRONT AND DIXIE LATE TONIGHT INTO TOMORROW  
NIGHT.  
 
WITH HEIGHT FALLS AND UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE  
APPROACH OF THIS SYSTEM REACHING UTAH LATE TOMORROW AND CONTINUING  
INTO FRIDAY, PRECIPITATION CHANCES INCREASE SIGNIFICANTLY,  
ESPECIALLY FOR SOUTHERN AND CENTRAL UTAH. THERE IS SUFFICIENT  
INSTABILITY AND LAPSE RATES TO MENTION THE THREAT OF THUNDER  
DURING THIS PERIOD.  
 
SNOW LEVELS LOOK TO REMAIN ABOVE 6KFT FOR THE AREAS WITH THE BULK  
OF THE PRECIPITATION. SOUTHERN AND CENTRAL MOUNTAINS MAY SEE  
LOCALLY SIGNIFICANT ACCUMULATIONS AIDED BY SOUTH-SOUTHEAST  
OROGRAPHIC ENHANCEMENT TOMORROW NIGHT. MOST VALLEYS LOOK TO  
REMAIN RAIN OR A RAIN/SNOW MIX THROUGH THE SHORT TERM PERIOD. BEST  
BET FOR VALLEY SNOW ACCUMULATIONS WILL BE NORTH OF HANKSVILLE  
INTO PRICE AND ACROSS THE WESTERN UINTA BASIN.  
 
GIVEN THE CONVECTIVE NATURE OF PRECIPITATION, LCL LOWERING TO NEAR  
850MB, AND WARM CLOUD DEPTH INCREASING TO 3-4KFT, LOCALLY HEAVY  
RAINFALL WILL BE POSSIBLE ACROSS SOUTHERN VALLEYS, ESPECIALLY LATE  
TOMORROW AFTERNOON INTO THURSDAY MORNING. THIS IS COINCIDENT WITH  
ANOMALOUSLY HIGH PRECIPITABLE WATER VALUES AS WELL.  
 
FRIDAY IS A TRANSITION DAY WITH THE TROUGH MAKING ITS WAY TO OUR  
NORTHEAST, ENCOURAGING BUILDING HEIGHTS AND WARMING ALOFT FROM  
SOUTHWEST TO NORTHEAST DURING THE AFTERNOON AND EVENING.  
 
DAY SHIFT MAY END UP LOOKING AT WINTER WEATHER ADVISORIES AND THE  
FLOOD THREAT EVEN FURTHER AS THE EVENT NEARS.  
   
LONG TERM (AFTER 00Z SATURDAY)
 
 
ACTIVE AND UNSETTLED WEATHER IS EXPECTED TO CONTINUE THROUGH THE  
FIRST HALF OF THE LONG TERM PERIOD PRIOR TO A PERIOD RIDGING  
EARLY/MID NEXT WEEK. IN LARGE GLOBALS CONTINUE TO ADVERTISE A  
RELATIVE BREAK LATER FRIDAY NIGHT THROUGH SATURDAY MORNING AS THE  
PREVIOUS LATE WEEK TROUGH LIFTS DOWNSTREAM AND NORTHEAST OF THE  
AREA, WHILE THE NEXT AMPLIFIES A BIT UPSTREAM ALONG THE NORCAL  
COAST. THE PROGRESSIVE NATURE OF THE PATTERN HOWEVER LOOKS TO SEE  
A DETERIORATION OF TRANQUIL CONDITIONS BY LATER SATURDAY AFTERNOON  
AS THIS UPSTREAM TROUGH MOVES INTO AND ACROSS THE EASTERN GREAT  
BASIN.  
 
DETERMINISTIC RUNS IN GLOBALS CONTINUE TO SHOW SPREAD IN  
AMPLITUDE/EVOLUTION OF THIS TROUGH, WITH THE EC DEEPER AND THE GFS  
MORE SHEARED AND OF LOWER AMPLITUDE...DIFFERENCES RELATING TO TIMING  
AND STRENGTH OF RIDGE AMPLIFICATION UPSTREAM OF THIS TROUGH. THIS  
SAID, ALL SIGNALS POINT TO INCREASED AREAL COVERAGE OF SHOWERS (MTN  
SNOW/VALLEY RAIN) FROM WEST-EAST LATE SATURDAY THROUGH MUCH OF  
SUNDAY, WITH EVENTUAL DRYING FROM SW-NE BY SUNDAY NIGHT AS THE RIDGE  
BECOMES INCREASINGLY MORE DOMINANT LOCALLY. DYNAMICALLY SPEAKING  
THIS TROUGH IS NOT ADVERTISED TO BE OVERLY IMPRESSIVE, BUT BREADTH  
OF MOISTURE AND INCREASING LIKELIHOOD OF CONVECTION SHOULD SUPPORT  
MODEST PRECIP FOR SOME AREAS (ESPECIALLY NORTH).  
 
AS MENTIONED, THE RIDGE WILL CONTINUE TO BUILD INTO THE REGION  
THROUGH EARLY NEXT WEEK PROVIDING DRY/TRANQUIL CONDITIONS AND  
WARMING TREND TEMPS.  
 

 
   
AVIATION
 
 
OPERATIONAL WEATHER CONCERNS ARE EXPECTED TO REMAIN MINIMAL AT  
THE KSLC TERMINAL TODAY, WITH GENERALLY LIGHT AND VARIABLE WINDS  
THIS MORNING BECOMING NORTHERLY AROUND 18Z. A 30% CHANCE EXISTS  
THAT THE NORTHWESTERLY WINDS WILL BEGIN TO PREVAIL AS EARLY AS 16Z  
HOWEVER.  
 

 
   
SLC WATCHES/WARNINGS/ADVISORIES
 
 
UT...NONE.  
WY...NONE.  

 
 

 
 
SHORT TERM...10  
LONG TERM/AVIATION...MERRILL  
 
FOR MORE INFORMATION FROM NOAA'S NATIONAL WEATHER SERVICE VISIT...  
HTTP://WEATHER.GOV/SALTLAKECITY  
 
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION  
VISIT...  
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab UT Page
The Nexlab ID Page
The Nexlab WY Page Main Text Page