299
FXUS65 KBOI 110912
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
312 AM MDT SUN MAY 11 2025
SHORT TERM...TODAY THROUGH TUESDAY NIGHT
AN UPPER-LEVEL LOW
APPROACHING THE PACIFIC NORTHWEST TODAY WILL CONTINUE TO PROVIDE
FAVORABLE CONDITIONS FOR SHOWERS AND THUNDERSTORMS. THE MAIN
CONCERN REMAINS THE THREAT OF STRONG WIND GUSTS THIS AFTERNOON
AND EVENING, PARTICULARLY ACROSS THE WESTERN MAGIC VALLEY, CAMAS
PRAIRIE, AND EASTERN BOISE MOUNTAINS. EARLY THIS MORNING, RADAR
SHOWED MOSTLY VIRGA ACROSS SOUTHWEST IDAHO WITH A FEW LIGHTNING
STRIKES OBSERVED IN OWYHEE COUNTY. THIS ACTIVITY APPEARS TO BE
TIED TO A WEAK EMBEDDED SHORTWAVE ROTATING NORTHEAST THROUGH THE
AREA AND SHOULD DIMINISH SHORTLY AFTER SUNRISE AS THE WAVE
EXITS.
ANOTHER ROUND OF THUNDERSTORMS IS EXPECTED TO DEVELOP THIS
AFTERNOON AND EVENING. OVERALL SETUP REMAINS SIMILAR TO
SATURDAY, WITH DEEPLY MIXED BOUNDARY LAYERS AND A STRONG LOW-
LEVEL JET SUPPORTING THE POTENTIAL FOR SPORADIC SEVERE WIND
GUSTS—MAINLY FROM TWIN FALLS COUNTY THROUGH THE CAMAS PRAIRIE.
STORMS ARE EXPECTED TO INITIATE AROUND 2 PM AND MOVE QUICKLY
NORTHEAST. THERE IS A 5% CHANCE OF GUSTS REACHING 60 MPH.
FURTHER WEST, DYNAMICS AND MOISTURE INCREASE SIGNIFICANTLY
ACROSS CENTRAL AND NORTHEAST OREGON BY EARLY EVENING. WHILE
HIGH-RES GUIDANCE KEEPS THE STRONGEST INSTABILITY AND SHEAR
NORTH AND WEST OF HARNEY AND BAKER COUNTIES, A FEW STORMS COULD
DRIFT EAST INTO THESE AREAS AFTER 6 PM—ESPECIALLY IF THE UPPER
LOW PROGRESSES SLIGHTLY FARTHER EAST THAN CURRENTLY FORECAST.
THE STRONGEST STORMS WILL BE CAPABLE OF GUSTY OUTFLOW WINDS AND
POSSIBLY SMALL HAIL.
STRONG SOUTHWESTERLY FLOW ALOFT (35–50 KT AT 10KFT MSL) WILL
MIX TO THE SURFACE STARTING LATE MORNING, LEADING TO WIDESPREAD
WINDY CONDITIONS THROUGH THE EVENING. WINDS WILL BE STRONGEST
ACROSS SOUTHEAST OREGON AND SOUTHWEST IDAHO SOUTH OF THE SNAKE
PLAIN, WHERE GUSTS OF 40–50 MPH ARE EXPECTED. BLOWING DUST WILL
BE POSSIBLE, PARTICULARLY ALONG HWY 95 AND HWY 51. A WIND
ADVISORY REMAINS IN EFFECT FOR HARNEY, MALHEUR, AND OWYHEE
COUNTIES THIS AFTERNOON AND EVENING.
ON MONDAY, THE UPPER TROUGH AXIS PUSHES INLAND, BRINGING AN
INCREASING CHANCE FOR SHOWERS FROM WEST TO EAST. BAKER AND
HARNEY COUNTIES WILL SEE THE HIGHEST POPS (60–80%), WITH LOWER
PROBABILITIES FARTHER EAST ACROSS SOUTHWEST IDAHO DUE TO TROUGH
ELONGATION. MODEST INSTABILITY MAY SUPPORT A FEW THUNDERSTORMS
OVER SOUTHEAST OREGON MONDAY AFTERNOON. WINDS WILL REMAIN BREEZY
WITH GUSTS OF 20–30 MPH. SHOWER CHANCES LINGER ACROSS HIGHER
TERRAIN MONDAY NIGHT (20–30%) AS THE UPPER TROUGH SLIDES INTO
EASTERN OREGON. HIGHS WILL COOL TO JUST BELOW NORMAL. BY
TUESDAY, THE UPPER TROUGH MOVES OVERHEAD, BRINGING A 30–50%
CHANCE OF SHOWERS AND THUNDERSTORMS. TUESDAY LOOKS TO BE THE
COOLEST DAY OF THE WEEK, WITH VALLEY HIGHS RUNNING ROUGHLY 10
DEGREES BELOW NORMAL.
LONG TERM...WEDNESDAY THROUGH SUNDAY
AN UPPER LOW WILL EXIT THE
AREA ON WEDNESDAY, AND A SHORTWAVE ON THE BACKSIDE OF THE TROUGH
WILL ALLOW FOR A 20-30% CHANCE OF PRECIPITATION THAT AFTERNOON
ALONGSIDE SOME BREEZY NW WINDS. LINGERING INSTABILITY WEDNESDAY
AFTERNOON COULD POP UP A FEW THUNDERSTORMS IN THE EASTERN PERIPHEREE
OF OUR CWA. WITH SNOW LEVELS STILL 6000-7000 FT MSL LIGHT SNOW
ACCUMULATIONS ARE POSSIBLE ON HIGHER PEAKS.
WEAK UPPER LEVEL RIDGING WILL BRING SLIGHTLY WARMER AND DRIER
CONDITIONS ON THURSDAY. AFTER THE BRIEF BREAK, A WEAK TROUGH FRIDAY
WILL LEAD INTO ANOTHER ACTIVE PERIOD. 30% PRECIPITATION CHANCES OVER
HIGHER TERRAIN ON FRIDAY INCREASE TO 40-60% AREA WIDE SATURDAY
AFTERNOON AS DEEP ALASKAN LOW MOVES IN. THIS WILL COOL TEMPS AFTER
THE BRIEF RIDGE ON THURSDAY, KEEPING TEMPS NEAR TO A FEW DEGREES
BELOW NORMAL THROUGH MOST OF THE LONG TERM.
AVIATION
MAINLY VFR THIS MORNING. DISSIPATING SHOWERS AND STORMS
ARE STILL PUTTING OUT OUTFLOW GUSTS, WITH REDUCTIONS TO MVFR/IFR
POSSIBLE IN MOUNTAIN SHOWERS. COLD FRONTAL PASSAGE ON SUNDAY WILL
BRING WIDESPREAD GUSTY WINDS WITH SHOWERS IN NE OR AND STORMS IN S-
CENTRAL ID. SMALL HAIL AND OUTFLOW GUSTS UP TO 60 MPH ARE POSSIBLE
IN STORMS NEAR THE MAGIC VALLEY. SURFACE WINDS: VARIABLE LESS THAN
10 KT, BECOMING SW 10-20 KT WITH GUSTS 30-45 KT THIS AFTERNOON.
STRONGEST WINDS ALONG RIDGES. SURFACE WINDS SE-SW 5-15 KT. WINDS
ALOFT AT 10KFT MSL: SW 30-40 KT.
KBOI...VFR. SCATTERED SHOWERS AND VIRGA, STRAY 20KT OUTFLOW GUSTS
ARE POSSIBLE. PRECIPITATION DISSIPATING BY SUN/10Z. WINDS SE 5-15
KT, BECOMING S 16-22 KT WITH GUSTS UP TO 35 KT THIS AFTERNOON.
BOI WATCHES/WARNINGS/ADVISORIES
ID...WIND ADVISORY FROM NOON TODAY TO MIDNIGHT MDT TONIGHT
IDZ015-029.
OR...WIND ADVISORY FROM NOON MDT /11 AM PDT/ TODAY TO MIDNIGHT MDT
/11 PM PDT/ TONIGHT ORZ061-063.
WWW.WEATHER.GOV/BOISE
INTERACT WITH US VIA SOCIAL MEDIA:
WWW.FACEBOOK.COM/NWSBOISE
WWW.X.COM/NWSBOISE
SHORT TERM...JDS
LONG TERM....JM
AVIATION.....JM
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