916
FXUS65 KBOI 010259
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
859 PM MDT MON MAR 31 2025
DISCUSSION
AN UPPER LEVEL TROUGH REMAINS OVER THE PACIFIC NW
WITH SEVERAL SHORTWAVES EMBEDDED IN THE FLOW. ONE SHORTWAVE OVER
EASTERN OR IS FORECAST TO SLOWLY MOVE EASTWARD TONIGHT INTO
SOUTHWEST ID ON TUESDAY MORNING, BRINGING SCATTERED SHOWERS,
SOME OF WHICH MAY PRODUCE A QUICK INCH OF SNOW UNDERNEATH THE
CORE. MODELS HAVE TRENDED UPWARD WITH QPF AND POPS SO HAVE
UPDATED THE FORECAST TO REFLECT THIS. SNOW LEVELS FALL TO THE
VALLEY FLOORS BY TUESDAY MORNING. COLD AIR ALOFT REMAINS OVER
THE AREA, WITH H500 TEMPERATURES AROUND -30C THROUGH TUESDAY,
WHICH IS FAVORABLE FOR SHOWER DEVELOPMENT TO CONTINUE. DAYTIME
HEATING ON TUESDAY WILL STRENGTHEN SHOWERS DURING THE AFTERNOON,
ESPECIALLY OVER THE HIGHER TERRAIN, WHERE SHOWERS MAY PRODUCE
THUNDER AND GRAUPEL. REST OF THE FORECAST ON TRACK WITH COOL AND
UNSETTLED CONDITIONS THROUGH FRIDAY, BEFORE WARMING OVER THE
WEEKEND TO AROUND 10 DEGREES ABOVE NORMAL OVER THE WEEKEND.
AVIATION
MAINLY VFR. SCATTERED RAIN AND SNOW SHOWERS WILL
CONTINUE OVERNIGHT. SHOWERS DECREASING AFTER 01/12Z, WITH ADDITIONAL
SHOWER AND ISOLATED THUNDERSTORM DEVELOPMENT MAINLY OVER THE HIGHER
TERRAIN DURING THE DAY TUESDAY. SNOW LEVELS 2500-3500 FT MSL.
PERIODS OF MVFR CONDITIONS IN RAIN WITH MVFR/IFR IN SNOW. MOUNTAINS
OBSCURED AT TIMES. SURFACE WINDS: SW-NW 5-15 KT. GUSTS TO 30 KT IN
THE MAGIC VALLEY ON TUESDAY. WINDS ALOFT AT 10KFT: W-NW 15-30 KT.
KBOI...MAINLY VFR. A 50% CHANCE OF SHOWERS OVERNIGHT, ENDING BY
01/15Z. RAIN SHOWERS MAY MIX WITH OR CHANGE TO SNOW OVERNIGHT. MVFR
CONDITIONS IN RAIN, ALTHOUGH IFR IS POSSIBLE IF PRECIP CHANGES TO
SNOW. SURFACE WINDS: NW 5-10 KT.
HYDROLOGY
MOST RIVER LEVELS CONTINUE TO GRADUALLY FALL DUE TO
THE COOLER TEMPERATURES. THIS DOES NOT INCLUDE INCREASED FLOWS
DOWNSTREAM FROM CONTROLLED RESERVOIR RELEASES, SUCH AS THE
OWYHEE RIVER BELOW OWYHEE DAM. FLOOD WARNINGS REMAIN IN EFFECT
FOR THE SILVIES RIVER NEAR BURNS AND THE MALHEUR RIVER NEAR
VALE.
PREV DISCUSSION
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...FIRST ROUND OF
SHOWERS AND THUNDERSTORMS THAT ROLLED THROUGH SW IDAHO PRODUCED
WIND GUSTS TO 50 MPH, AND LOTS OF SMALL HAIL WHICH COVERED THE
GROUND ON SOME AREAS, INCLUDING THE BOISE METRO. THAT AREA OF
CONVECTION WILL MOVE OUT OF THE AREA LATER THIS AFTERNOON AS A
NEW AREA OF CONVECTION DEVELOPS IN SE OREGON. THE HI-RES MODELS
CONTINUE TO INDICATE THE POTENTIAL FOR SMALL HAIL AND GUSTY
WINDS WITH THE HEAVIER SHOWERS AND THUNDERSTORMS AS THEY
PROPAGATE INTO SW IDAHO LATE THIS AFTERNOON AND EVENING. THE
HIGHER ELEVATIONS COULD SEE BRIEF BURSTS OF MODERATE TO HEAVY
SNOWFALL THAT COULD DROP A QUICK INCH OR TWO OF SNOWFALL. THE
TREND OVERALL WILL BE A DECREASE IN ACTIVITY TONIGHT, BUT
INCREASE AGAIN ON TUESDAY DUE INSTABILITY FROM DAYTIME
HEATING/COLD AIR ALOFT. THERE IS ALSO A SLIGHT CHANCE OF
AFTERNOON THUNDERSTORMS, ONCE AGAIN ACCOMPANIED BY GUSTY WINDS,
SMALL HAIL/GRAUPEL, AND BRIEF PRECIP (INCLUDING SNOW ABOVE 3500
FEET). THE TROUGH LINGERS ON WEDNESDAY FOR MORE SHOWERS, MAINLY
OVER THE HIGHER ELEVATIONS, BUT THE PROBABILITY OF
PRECIPITATION IS LOWER (GENERALLY 15-40 PERCENT). THERE IS ALSO
A SLIGHT CHANCE OF AFTERNOON THUNDERSTORMS IN S-CENTRAL IDAHO.
TEMPERATURES REMAIN 5 TO 10 DEGREES BELOW NORMAL EACH DAY.
LONG TERM...THURSDAY THROUGH MONDAY...THE FINAL PIECE OF THE
UPPER LEVEL TROUGH AXIS WILL PASS BY THURSDAY AS A STRONG RIDGE
MOVES IN FROM THE WEST. AFTER A 20-60% CHANCE OF SHOWERS THU
(HIGHEST IN THE MOUNTAINS), THEY WILL END LATE THURSDAY NIGHT.
SNOW LEVELS WILL RANGE FROM 3000-4000 FT MSL THU INTO THU NIGHT.
DRY WEATHER WILL BE WITH US FRIDAY THROUGH MONDAY AS THE RIDGE
MOVES CLOSER THROUGH THE WEEKEND, AND THEN OFF TO THE EAST
MONDAY.
TEMPERATURES WILL START OUT CHILLY - AROUND 5 DEGREES BELOW
NORMAL THURSDAY, BUT QUICKLY WARM UP. WE SHOULD BE NEAR NORMAL
FRIDAY, A FEW DEGREES ABOVE NORMAL SATURDAY, AND 10-15 DEGREES
ABOVE NORMAL SUNDAY AND MONDAY. MODELS ARE IN EXCELLENT
AGREEMENT ON THIS PATTERN, SO THIS IS A HIGH-CONFIDENCE
FORECAST.
BOI WATCHES/WARNINGS/ADVISORIES
ID...NONE.
OR...NONE.
WWW.WEATHER.GOV/BOISE
INTERACT WITH US VIA SOCIAL MEDIA:
WWW.FACEBOOK.COM/NWSBOISE
WWW.X.COM/NWSBOISE
DISCUSSION...KA
AVIATION.....ST
SHORT TERM...BW
LONG TERM....SP
HYDROLOGY....BW
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page