Weather Service Report


361 
FXUS65 KRIW 182049
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
249 PM MDT FRI APR 18 2014

.SHORT TERM...TONIGHT AND SATURDAY

STRONG COLD FRONT MOVING TO NEAR THE CONTINENTAL DIVIDE ATTM WITH 
STRONG SW WINDS AHEAD OF IT AND COLDER RAIN AND SNOW SHOWERS BEHIND 
IT. COLD ENOUGH IN THE STAR VALLEY FOR A QUICK CHANGEOVER TO SNOW 
WITH UP TO A QUICK INCH REPORTED. JACKSON VALLEY STAYED RAIN WITH 
RAINFALL AMOUNTS GENERALLY BETWEEN .15 AND .30 INCHES. WINDS ARE 
SURFACING EAST OF THE DIVIDE IN MANY AREAS WITH WIND GUSTS OF 40 TO 
50 MPH IN QUITE A FEW AREAS AND LOCALIZED GUSTS BETWEEN 55 AND 60 
MPH. SOME AREAS WILL FLIRT WITH OR BRIEFLY TOUCH HIGH WIND THROUGH 
00Z OR A LITTLE LATER IN THE CENTRAL ZONES. SPS IS COVERING THESE 
AREAS. THERE WILL BE A FEW RAIN SHOWERS WITH FROPA EAST OF THE 
DIVIDE BUT THEY WILL BE JUST ISOLATED IN MANY AREAS WITH THE DRY 
AIRMASS AHEAD OF IT. THE NORTHERN ZONES HOWEVER...HAVE A LITTLE LOW 
LEVEL MOISTURE TO WORK WITH SO A BETTER SHOT THERE ALONG WITH AN 
ISOLATED THUNDERSTORM STILL POSSIBLE BUT NOT NECESSARILY LIKELY. 
SECONDARY FRONT THAT DROPS DOWN BEHIND THE WEAKENING UPPER 
LOW/SHORTWAVE TONIGHT WITH BOUNDARY LAYER MOISTENING UP QUITE A BIT 
IN NATRONA COUNTY. COULD BE ENOUGH FOR LOW CLOUDS OR PATCHY FOG SO 
INDICATED THIS IN THE FORECAST AROUND SUNRISE. AND WITH THE RECENT 
RAIN AND SNOW OUT WEST...WILL ADD SOME LOW CLOUDS AND FOG TO THE 
JACKSON AND STAR VALLEYS FOR LATER TONIGHT THROUGH 15Z SATURDAY. ON 
SATURDAY...SOME CONVECTION IS POSSIBLE ACROSS SWEETWATER COUNTY AS 
FRONT BOUNDARY STALLS OUT DOWN THERE AND THEN A LITTLE BIT OF 
MOISTURE AND VERY WEAK FORCING IS PROVIDED FROM A SYSTEM WELL TO OUR 
SOUTH. SCATTERED HIGHER TERRAIN SHOWERS ARE CERTAINLY A 
POSSIBILITY...MORE ISOLATED ON THE RED DESERT FLOOR. TEMPERATURES 
WILL NOT BE QUITE AS WARM TOMORROW EAST OF THE DIVIDE WHILE WEST OF 
THE DIVIDE...THEY'LL ACTUALLY BE WARMER WITHOUT THE PCPN.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY NIGHT

THE REST OF THE WEEKEND INTO MONDAY REMAINS RELATIVELY QUIET...WITH 
A WEAK COLD FRONT MOVING THROUGH THE AREA SUNDAY MORNING. ISOLATED 
SHOWERS AND AN ISOLATED THUNDERSTORM WILL BE POSSIBLE ACROSS 
SOUTHERN PORTIONS SUNDAY...WITH DRY CONDITIONS ON MONDAY. 

A RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE NORTHERN ROCKIES INTO 
ALBERTA MONDAY...AND SLOWLY PROGRESS EASTWARD INTO THE HIGH PLAINS 
TUESDAY...AS THE NEXT STORM SYSTEM FROM THE NORTH PACIFIC DIGS 
SOUTHEASTWARD INTO NORTHERN CALIFORNIA AND THE GREAT BASIN. A 
DUMBBELL LOW WILL FORM BY 12Z WEDNESDAY AND PROGRESS EASTWARD OVER 
MONTANA...BEFORE EJECTING INTO THE NORTHERN PLAINS BY 18Z THURSDAY. 
NORTHWEST FLOW ALOFT WILL OCCUR IN THE STORMS WAKE...AS A RIDGE OF 
HIGH PRESSURE BUILDS BACK INTO THE AREA ON FRIDAY INTO SATURDAY. THE 
12Z GFS AND ECMWF HAVE COME MORE IN LINE WITH EACH OTHER THAN 
PREVIOUS RUNS. THIS IS A PROMISING SIGN FIVE DAYS OUT...SO WILL 
CONTINUE TO MONITOR ANY CHANGES AS THE STORM APPROACHES SHORE.  

ON TUESDAY...ISOLATED TO SCATTERED RAIN AND SNOW SHOWERS WILL ENTER 
WESTERN PORTIONS EARLY TUESDAY MORNING...INCREASING THROUGH THE DAY. 
ISOLATED THUNDERSTORMS WILL BE POSSIBLE BY THE AFTERNOON ACROSS MOST 
OF THE AREA...WITH MOST OF THE PRECIPITATION OCCURRING ACROSS 
WESTERN...SOUTHWESTERN AND NORTHERN PORTIONS. SOUTHWEST FLOW ALOFT 
WILL CREATE GUSTY WINDS DURING THE DAY AHEAD OF THE COLD FRONT 
ACROSS CENTRAL AND SOUTHERN PORTIONS...AND PUSHING AFTERNOON 
TEMPERATURES EAST OF THE DIVIDE INTO THE 70S AND POSSIBLY LOWER 
80S.   
        
ON WEDNESDAY...SNOW WILL FALL TUESDAY NIGHT INTO WEDNESDAY MORNING 
ACROSS THE WESTERN MOUNTAINS AND THE HIGHER ELEVATIONS OF THE 
BIGHORN MOUNTAINS. RAIN WILL SLOWLY CHANGE OVER TO SNOW ACROSS THE 
WESTERN VALLEYS AND BASINS...BECOMING ALL SNOW SHORTLY BEFORE DAWN. 
A RAIN/SNOW MIX WILL RETURN TO THESE AREAS BY LATE MORNING THROUGH 
THE REST OF THE DAY. RAIN/SNOW SHOWERS WILL ALSO OCCUR ACROSS 
SOUTHERN PORTIONS THROUGH MID MORNING BEFORE CHANGING OVER TO ALL 
RAIN. THE REST OF THE AREA CAN EXPECT ISOLATED TO SCATTERED RAIN 
SHOWERS THROUGH THE DAY. 

ON THURSDAY...SNOW WILL CONTINUE ACROSS THE WEST...WITH A FEW 
RAIN/SNOW SHOWERS MIXED IN LATER IN THE DAY. SNOW WILL FALL ACROSS 
SOUTHERN PORTIONS...BECOMING MORE ISOLATED AND CHANGING TO RAIN BY 
THE AFTERNOON. OVERALL...CHANCES FOR PRECIPITATION BECOME MORE 
ISOLATED THROUGHOUT THE DAY.

BY FRIDAY...LINGERING ISOLATED SHOWERS ACROSS THE WEST.  
OTHERWISE...COOLER AND DRY CONDITIONS.

&&

.AVIATION.../00Z ISSUANCE/

COLD FRONT WILL MOVE QUICKLY EAST OF THE DIVIDE THROUGH EVENING 
HOURS WITH A LOT OF WIND AND A FEW SHOWERS AND EVEN AN ISOLATED 
THUNDERSTORM POSSIBLE. SCATTERED MOUNTAIN OBSCURATION AND SNOW 
SHOWERS WILL PERSIST OUT WEST INTO THE EVENING BEFORE RETREATING TO 
THE HIGHER PEAKS. LOW CLOUDS AND PATCHY FOG MAY FORM IN THE JACKSON 
AND STAR VALLEYS OVERNIGHT AFFECTING THE KJAC TERMINAL WITH MVFR 
CONDITIONS. ANOTHER AREA OF LOW CLOUDS AND FOG MAY FORM OVER NATRONA 
COUNTY BY LATER TONIGHT AFFECTING THE KCPR TERMINAL BY SUNRISE. 
OTHERWISE...EXPECT VFR CONDITIONS IN MOST AREAS WITH WINDS 
DECREASING LATER TONIGHT. ON SATURDAY...SCATTERED SHOWERS AND 
ISOLATED THUNDERSTORMS ARE EXPECTED IN THE FAR SOUTH INCLUDING KRKS. 
OTHER AREAS WILL BE DRY WITH VFR CONDITIONS AND LESS WIND. STILL 
BREEZY TO LOCALLY WINDY BUT NOT AS STRONG AS TODAY.

&&

.FIRE WEATHER...

A STRONG COLD FRONT WILL CONTINUE MOVING ACROSS CENTRAL WYOMING THIS 
AFTERNOON WITH STRONG WEST TO SOUTHWEST WINDS OF 40 TO 50 MPH AND 
ISOLATED TO WIDELY SCATTERED SHOWERS. THUNDERSTORMS...IF ANY...WILL 
BE VERY ISOLATED AND MAINLY CONFINED TO THE NORTHEAST PART OF THE 
DISTRICT. MOUNTAIN SNOW SHOWERS OUT WEST WILL DIMINISH AND RETREAT 
TO THE HIGHER PEAKS WITH TIME TONIGHT. SATURDAY WILL NOT BE AS WINDY 
BUT STILL BREEZY TO LOCALLY WINDY...ESPECIALLY THE MOUNTAIN AND 
FOOTHILL AREAS. THERE WILL BE SCATTERED SHOWERS AND ISOLATED 
THUNDERSTORMS IN SWEETWATER COUNTY...ESPECIALLY SOUTH OF INTERSTATE 
80 SATURDAY AFTERNOON.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE. 

&&

$$

SHORT TERM...SKRBAC
LONG TERM...LAVOIE
AVIATION...SKRBAC
FIRE WEATHER...SKRBAC







Return to Home page


Western Regional Climate Center, wrcc@dri.edu