217  
FXUS65 KRIW 301732  
AFDRIW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE RIVERTON WY  
1132 AM MDT SUN MAR 30 2025  
   
KEY MESSAGES  
 
- PRECIPITATION WILL BE WIDESPREAD ALONG AND EAST OF THE  
CONTINENTAL DIVIDE THIS MORNING. AREAS OF SNOW CONTINUE THIS  
MORNING WITH A CHANGEOVER TO A RAIN SNOW MIX THIS AFTERNOON.  
MOUNTAIN AREAS WILL REMAIN ALL SNOW.  
 
- A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE BIGHORN  
MOUNTAINS AND THE ABSAROKAS FOR ADDITIONAL SNOW AMOUNTS OF  
1-4 INCHES.  
 
- SHOWERS AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE FOR MUCH  
OF THE FORECAST AREA MONDAY AND TUESDAY, WITH LIGHT SNOW  
OVERNIGHT, ESPECIALLY WESTERN AND NORTHERN PORTIONS.  
 
- THE ACTIVE WEATHER PATTERN CONTINUES THROUGH THE MIDDLE OF THE  
WEEK, BUT PRECIPITATION CHANCES WILL DECREASE HEADING INTO THE  
LATTER HALF OF THE WEEK AS HIGH PRESSURE SETTLES IN THIS  
UPCOMING WEEKEND.  
 
- TEMPERATURES WILL REMAIN COOL THROUGH THIS WEEK AND BEGIN TO  
INCREASE BY NEXT SUNDAY.  
 
 
   
UPDATE  
 
ISSUED AT 1053 AM MDT SUN MAR 30 2025  
 
THE LOW IS SLIDING NORTHEAST THROUGH CENTRAL WYOMING THIS MORNING,  
WHICH IS RIGHT ON TRACK. AN AREA OF MODERATE SNOWFALL DEVELOPED ON  
THE NORTH SIDE OF THIS LOW AND DROPPED A FEW INCHES OF SNOW IN THE  
WIND RIVER BASIN AND CONTINUES TO DROP SNOW IN THE BIGHORN BASIN UP  
INTO THE ABSAROKA MOUNTAINS THIS MORNING. MOST LOCATIONS ONLY HAD  
SNOW ACCUMULATE ON ELEVATED SURFACES AND IN THE GRASS, BUT THERE WAS  
ABOUT AN INCH OF SLUSHY SNOW ON ROADWAYS IN SOME LOCATIONS. THIS  
SLUSH WILL MELT AS THE SNOW PUSHES NORTHEAST OUT OF THE AREA THIS  
AFTERNOON AND SKIES CLEAR A BIT. WILL BE EXTENDING THE WINTER  
WEATHER ADVISORY FOR THE ABSAROKA MOUNTAINS UNTIL 6 PM THIS EVENING  
AS CONVECTIVE SNOW SHOWERS ARE LIKELY (70%) TO DEVELOP THIS  
AFTERNOON AND RESULT IN A FEW MORE INCHES OF SNOW ALONG THE EASTERN  
SLOPES OF THE ABSAROKA MOUNTAINS. THE WINTER WEATHER ADVISORY FOR  
THE EASTERN SLOPES OF THE WIND RIVER MOUNTAINS WILL BE ALLOWED TO  
EXPIRE AT NOON TODAY AS SNOW HAS ALL BUT ENDED THERE. THE WINTER  
WEATHER ADVISORY FOR THE BIGHORNS WILL REMAIN IN EFFECT UNTIL 6 PM  
THIS EVENING AS ANOTHER FEW INCHES OF SNOW WILL FALL THERE.  
 
 
   
DISCUSSION  
 
ISSUED AT 111 AM MDT SUN MAR 30 2025  
 
PRECIPITATION WILL CONTINUE (BASICALLY) ALONG AND EAST OF THE DIVIDE  
THROUGH THE REST OF THE MORNING, WHICH WOULD BE FROM YELLOWSTONE TO  
THE WIND RIVER MOUNTAINS AND FAR NORTHERN PORTIONS OF SWEETWATER  
COUNTY. SNOW WILL BE ONGOING OVER THESE AREAS THROUGH EARLY IN  
THE AFTERNOON, ALTHOUGH ACCUMULATIONS WILL BE CONFINED TO GRASSY  
AREAS AFTER SUNRISE. ADDITIONAL ISOLATED SHOWERS WILL REDEVELOP  
ACROSS THE FORECAST AREA, ESPECIALLY NORTHWESTERN PORTIONS,  
THROUGH THE AFTERNOON.  
 
A RIDGE WILL BUILD OVER THE REGION TONIGHT INTO MONDAY IRT ANOTHER  
STRONG UPPER LOW OFF THE PACNW COAST. THIS WILL KEEP PACIFIC  
MOISTURE STREAMING OVER THE REGION AND TROUGHS EJECTING FROM THIS  
SYSTEM MOVE OVER THE CWA. ADDITIONAL SHOWERS WILL REACH FAR WESTERN  
PORTIONS MONDAY MORNING, WITH ANOTHER ROUND OF SHOWERS DEVELOPING  
OVER SOUTHERN PORTIONS IN THE AFTERNOON. ISOLATED THUNDERSTORMS  
COULD OCCUR IN THESE AREAS THROUGH THE AFTERNOON. ISOLATED SHOWERS  
AND THUNDERSTORMS WILL ALSO BE POSSIBLE EAST OF THE DIVIDE, AS THE  
SHORTWAVE TROUGH MOVES EASTWARD. THIS ACTIVITY WILL CONTINUE THROUGH  
THE EVENING. SNOW LEVELS WILL AVERAGE BETWEEN 6000 AND 7000FT ACROSS  
MOST OF THE FORECAST AREA, BUT AGAIN ANY SNOW THAT FALLS DURING THE  
DAY WILL HAVE LITTLE TO NO IMPACT AND ACCUMULATE IN GRASSY AREAS.  
 
THE AFOREMENTIONED SHORTWAVE TROUGH WILL SLOW DOWN MONDAY NIGHT AND  
BECOME BETTER ORGANIZED INTO A MIDLEVEL LOW, DROPPING TEMPERATURES  
AND ALLOW FOR RAIN TO CHANGE OVER TO SNOW OVER WESTERN PORTIONS.  
THIS ACTIVITY WILL CONTINUE THROUGH MUCH OF THE DAY TUESDAY, AS THE  
LOW SLOWLY MOVES OVER THE BIGHORN BASIN AND JOHNSON/NATRONA  
COUNTIES. AS A RESULT, MOST OF THE PRECIPITATION OVER NORTHERN  
PORTIONS WILL OCCUR UNDER A DEVELOPING BAROCLINIC LEAF FROM THE  
MIDLEVEL LOW. RAIN/SNOW TO SNOW WILL PUSH INTO NORTHERN PORTIONS OF  
THE BIGHORN BASIN AND NORTHERN JOHNSON COUNTY TUESDAY EVENING. THIS  
ACTIVITY WILL SPREAD SOUTHWARD THROUGH THE NIGHT AS THE LOW TRACKS  
OVER THE BLACK HILLS.  
 
FORECAST DETAILS BECOME LESS CLEAR BY WEDNESDAY. SHOWERS REMAIN  
POSSIBLE FOR MUCH OF THE AREA, BUT WILL BE DEPENDENT ON HOW MUCH  
INFLUENCE FROM THE EXITING LOW/STORM REMAINS. ADDITIONALLY, THE  
REMNANTS FROM THE PACNW LOW LOOK TO DIVE SOUTHWARD OVER THE FOUR  
CORNERS REGION, SO FORECAST DETAILS ARE HIGHLY IN FLUX THROUGH THE  
REST OF THE PERIOD. NO CLEAR SIGNAL FOR WET CONDITIONS TO CONTINUE  
OR MORE DRIER CONDITIONS TO OCCUR.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z MONDAY/  
 
ISSUED AT 1130 AM MDT SUN MAR 30 2025  
 
THE LATEST SHORTWAVE WILL CONTINUE TO EXIT THE REGION. WIDESPREAD  
SNOW AND LOW CLOUDS CONTINUE TO EXIST ACROSS EAST OF THE DIVIDE  
TERMINALS, WITH KCPR, KCOD, AND KWRL EXPECTED TO HOLD ONTO IFR CIGS  
THROUGH THE AFTERNOON. OVERALL, HOWEVER, CONDITIONS WILL GRADUALLY  
IMPROVE ACROSS ALL TERMINALS THROUGH THE AFTERNOON AND EVENING WITH  
PREVAILING VFR FOR MOST TERMINALS AFTER 06Z MONDAY.  
 
THE NEXT SHORTWAVE WILL MOVE INTO THE REGION LATE IN THE PERIOD  
HOWEVER, WITH WEST OF THE DIVIDE TERMINALS STARTING TO SEE MVFR/IFR  
IMPACTS AFTER SUNRISE MONDAY MORNING. ANY PRECIPITATION MONDAY WILL  
BE SHOWERY IN NATURE AND THUS IT IS HARD TO PINPOINT EXACT TIMING  
AND LOCATIONS. AHEAD OF THIS NEXT SHORTWAVE, HI-RES MODELS DO  
INDICATE THAT THERE WILL BE SOME INITIAL CONVECTION OVERNIGHT  
TONIGHT. MOST LIKELY IMPACTS FROM THIS INITIAL PUSH OF MOISTURE  
WOULD BE AT KJAC (30% CHANCE) AND KBPI AND KPNA (15-30% CHANCES).  
OCCASIONAL MVFR CONDITIONS ARE POSSIBLE (20% CHANCE) WITH THESE  
SHOWERS.  
 
PLEASE SEE THE AVIATION WEATHER CENTER AND/OR CWSU ZDV AND ZLC FOR  
THE LATEST INFORMATION ON ICING AND TURBULENCE FORECASTS.  
 
 
   
RIW WATCHES/WARNINGS/ADVISORIES  
 
WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR WYZ002-015.  
 
WINTER WEATHER ADVISORY UNTIL 6 PM MDT THIS EVENING FOR WYZ009.  
 
 
 
 
 
UPDATE...ROWE  
DISCUSSION...LAVOIE  
AVIATION...HENSLEY  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab WY Page
Main Text Page