541
FXUS65 KRIW 271026
AFDRIW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
426 AM MDT FRI MAR 27 2026
KEY MESSAGES
- LOW CLOUDS AND DREARY CONDITIONS WILL CONTINUE ALONG THE I-25
CORRIDOR FROM CASPER TO BUFFALO THROUGH THIS MORNING.
- ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS RETURN THIS
WEEKEND AND MONDAY AS TEMPERATURES WARM BACK UP TO WELL ABOVE
NORMAL.
- A COLD FRONT WILL MOVE OVER THE AREA MONDAY NIGHT INTO TUESDAY
MORNING. CHANCES FOR LIGHT SNOW OVER THE WESTERN AND NORTHERN
MOUNTAINS. ANY SNOW THAT COULD OCCUR IN THE LOWER ELEVATIONS
WILL MELT TUESDAY.
- A WEATHER PATTERN CHANGE IS FINALLY EXPECTED TO OCCUR TOWARD
THE LATTER HALF OF NEXT WEEK, WITH CHANCES FOR PRECIPITATION
AND COOLER TEMPERATURES FAVORED.
DISCUSSION
ISSUED AT 140 AM MDT FRI MAR 27 2026
LOW CLOUDS WILL REMAIN IN PLACE OVER AREAS EAST OF THE DIVIDE THIS
MORNING. IT WILL BE A CHILLY START (GIVEN THE RECENT TREND OF ABOVE
NORMAL TEMPERATURES) THIS MORNING WITH TEMPERATURES IN THE 20S TO
MIDDLE 30S. IT WILL BE A PLEASANT DAY WITH DRY CONDITIONS, LIGHT
WINDS AND HIGHS IN THE 50S TO LOWER 60S (THIS IS STILL SLIGHTLY
ABOVE NORMAL FOR LATE MARCH). THE ONLY DOWNSIDE WILL BE HIGH CLOUDS
STREAMING OVER THE AREA FROM WEST TO EAST.
DRY CONDITIONS WILL CONTINUE OVER THE WEEKEND AS A BROAD FLAT RIDGE
BUILDS OVER THE NORTHERN ROCKIES. THIS WILL RESULT IN A PERSISTENT
WESTERLY FLOW ALOFT, WHICH WILL ALSO LEAD TO A LEESIDE TROUGH OVER
EASTERN PORTIONS OF THE STATE. THIS WILL TIGHTEN THE PRESSURE
GRADIENT AND CAUSE WESTERLY WINDS OF 25 TO 35 MPH OVER MUCH OF THE
CWA. MOST OF JOHNSON COUNTY AND EASTERN PORTIONS OF THE BIGHORN
BASIN WILL NOT BE AFFECTED BY THESE WINDS. ADDITIONALLY, RH VALUES
WILL BE CRITICALLY LOW FOR MOST LOWER ELEVATION ZONES SATURDAY AND
SUNDAY. ABOVE NORMAL TO RECORD TEMPERATURES WILL ALSO RETURN ACROSS
THE AREA. THESE CONDITIONS RETURN FOR MONDAY AS WELL, WITH WINDS
INCREASING AND BECOMING MORE WIDESPREAD ACROSS THE CWA AS A TROUGH
AND ASSOCIATED COLD FRONT APPROACH FROM THE NORTHWEST. CHANCES FOR
PRECIPITATION WILL INCREASE OVER NORTHWESTERN PORTIONS THROUGH THE
DAY MONDAY, WITH SNOW LEVELS AROUND 7000FT. THUS, WILL ISSUE FIRE
WEATHER WATCHES FOR SATURDAY SUNDAY AND MONDAY.
CHANCES FOR PRECIPITATION MONDAY NIGHT INTO TUESDAY MORNING WILL BE
MAINLY CONFINED TO WESTERN AND NORTHERN PORTIONS. SNOW LEVELS WILL
CONTINUE TO DROP, REACHING AT LEAST 6000FT. ANY SNOW THAT MAY FALL
IN THE LOWER ELEVATIONS MONDAY NIGHT WILL MELT AFTER SUNRISE TUESDAY
MORNING DUE TO THE RISING MARCH SUN ANGLE. OTHERWISE, SNOWFALL
AMOUNTS IN THE NORTHERN AND WESTERN MOUNTAINS ARE RATHER LIGHT SO
FAR, RANGING BETWEEN 2 TO 5 INCHES.
DRY CONDITIONS RETURN FOR WEDNESDAY, AS THIS SYSTEM WILL QUICKLY
EXIT EASTWARD OVER THE CENTRAL/NORTHERN PLAINS. MODELS REMAIN SPLIT
WITH THE NEXT STORM SYSTEM FROM THURSDAY INTO NEXT SATURDAY.
CONFIDENCE CONTINUES TO FAVOR THE ECMWF SOLUTION, WHICH DIGS A
LONGWAVE TROUGH OVER THE INTERMOUNTAIN WEST. THIS WILL INCREASE
SOUTHWEST FLOW ALOFT OVER THE COWBOY STATE THURSDAY, WITH INCREASING
CHANCES FOR PRECIPITATION THURSDAY AND FRIDAY AS THE BASE OF THE
TROUGH (WITH A CLOSED LOW) BOTTOMS OUT OVER THE GREAT BASIN. WILL
CONTINUE TO KEEP AN EYE ON THIS SYSTEM WITH FINGERS CROSSED FOR THE
MUCH NEEDED PRECIPITATION.
AVIATION /12Z TAFS THROUGH 12Z SATURDAY/
ISSUED AT 423 AM MDT FRI MAR 27 2026
MOST TERMINALS WILL HAVE LARGELY VFR CONDITIONS THROUGH THE
PERIOD WITH WIND GENERALLY 12 KNOTS OR LESS. THE EXCEPTION WILL
BE IN VICINITY OF KCPR WHERE EASTERLY FLOW WILL BRING MVFR
CEILINGS THROUGH AROUND 15Z BEFORE BEGINNING TO SCATTER OUT AND
VFR CONDITIONS RETURN. LOCAL WIND SHEAR MAY OCCUR IN VICINITY
OF KRIW AND KLND THROUGH AROUND 16Z THIS MORNING.
FIRE WEATHER
ISSUED AT 140 AM MDT FRI MAR 27 2026
CRITICAL FIRE WEATHER CONDITIONS EXPECTED TO RETURN SATURDAY AND
LAST THROUGH MONDAY. WEST WINDS WITH GUSTS OF 30 TO 35 MPH WILL
OCCUR FOR MUCH OF THE FORECAST AREA SATURDAY AND SUNDAY,
INCREASING TO 35 TO 50 MPH MONDAY AHEAD OF A COLD FRONT. RH
RECOVERY WILL BE FAIR TO POOR SATURDAY NIGHT AND SUNDAY NIGHT.
PRECIPITATION CHANCES WILL BE CONFINED TO FAR NORTHWESTERN
PORTIONS OF THE STATE DURING THE DAY MONDAY, WITH SNOW LEVELS
AROUND 7000FT. THE FRONT WILL MOVE THROUGH THE AREA MONDAY NIGHT
INTO TUESDAY MORNING.
RIW WATCHES/WARNINGS/ADVISORIES
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
EVENING FOR WYZ276>280-283-285-287-289-300.
DISCUSSION...LAVOIE
AVIATION...HATTINGS
FIRE WEATHER...LAVOIE
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