188
FXUS65 KBOI 192334
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
534 PM MDT TUE MAY 19 2026
UPDATE
UPDATED AVIATION DISCUSSION.
KEY MESSAGES
- MOSTLY DRY WITH TEMPERATURES WARMING THROUGH FRIDAY.
- WELL ABOVE NORMAL TEMPERATURES OVER MEMORIAL DAY WEEKEND.
GUSTY WINDS AND A FEW MOUNTAIN SHOWERS POSSIBLE ON MEMORIAL
DAY.
- TURNING COOLER EARLY NEXT WEEK WITH GUSTY WINDS AND INCREASING
CHANCE OF PRECIPITATION STARTING TUESDAY.
SHORT TERM /THROUGH THURSDAY NIGHT/
ISSUED 157 PM MDT TUE MAY 19 2026
OUR REGION WILL REMAIN POSITIONED ON THE WESTERN EDGE OF UPPER
LEVEL TROUGHING THROUGH THURSDAY. WHILE THE FOCUS OF ORGANIZED
PRECIPITATION WILL REMAIN TO OUR EAST, DAYTIME INSTABILITY WILL
SUPPORT WIDESPREAD CUMULUS BUILDUPS OVER THE MOUNTAINS AS SEEN
THIS AFTERNOON. THERE'S A SLIGHT CHANCE THAT SHOWERS COULD
DEVELOP FROM THE CUMULUS FIELD ACROSS E-CENTRAL OREGON AND
W-CENTRAL IDAHO MTNS EACH AFTERNOON. LOCALIZED GUSTY WINDS WILL
BE POSSIBLE FROM SHOWERS OR MORE ROBUST CUMULUS (WITH OR W/O
PRECIPITATION). SHOWER CHANCES BRIEFLY INCREASE TO 15-25% IN THE
W-CENTRAL IDAHO MTNS AND S-CENTRAL IDAHO ZONES WEDNESDAY NIGHT
IN RESPONSE TO A PASSING SHORTWAVE TROUGH. OTHERWISE IT'S DRY
AND TEMPERATURES ARE ON THE WAY UP, LEAVING BEHIND ANY
FROST/FREEZE CONCERNS FOR THE SNAKE PLAIN. BY THURSDAY HIGH
TEMPERATURES WILL BE SEVERAL DEGREES ABOVE NORMAL.
LONG TERM /FRIDAY THROUGH TUESDAY/
ISSUED 157 PM MDT TUE MAY 19 2026
A RIDGE OF HIGH PRESSURE WILL BUILD OVER THE WESTERN US BY THE
END OF THIS WEEK, BRINGING GENERALLY CLEAR, WARM AND DRY
CONDITIONS TO THE REGION THROUGH MONDAY. TEMPERATURES WILL BE
ABOUT 10-15 DEGREES ABOVE NORMAL. THE RIDGE WILL REACH PEAK
STRENGTH ON SUNDAY, WITH HIGH TEMPERATURES NEAR 90F IN THE
TREASURE VALLEY. BY MONDAY, MODELS INDICATE THAT AN UPPER LEVEL
LOW MOVING INTO THE PACIFIC NORTHWEST WILL BEGIN TO INCREASE
CHANCES FOR PRECIPITATION. THE UPPER LEVEL TROUGH WILL MOVE
INLAND ON TUESDAY, WITH ABOUT HALF OF THE MODELS SHOWING THAT
THE TROUGH WILL EVOLVE INTO A CLOSED LOW OVER THE PACIFIC NW BY
TUESDAY OR WEDNESDAY. IN EITHER SCENARIO, TEMPERATURES WILL COOL
DOWN 10-20 DEGREES BY TUESDAY INCREASING WINDS AND CHANCE OF
SHOWERS AND THUNDERSTORMS (20-30% CHANCE).
AVIATION /00Z WEDNESDAY THROUGH THURSDAY/
ISSUED 534 PM MDT TUE MAY 19 2026
VFR UNDER SCATTERED CUMULUS. ISOLATED VIRGA SHOWERS THIS
AFTERNOON CAPABLE OF PRODUCING LOCALIZED GUSTY WINDS. SURFACE
WINDS: SW-NW 5-15 KT WITH LOCALIZED GUSTS TO AROUND 20 KT THIS
AFTERNOON. BECOMING VARIABLE UNDER 10 KT OVERNIGHT. WINDS ALOFT
AT 10KFT MSL: W-NW 5-15 KT.
KBOI...VFR. SURFACE WINDS: NW 8-12 KT WITH GUSTS TO AROUND 18
KT THIS AFTERNOON AND WEDNESDAY AFTERNOON, LIGHT AND VARIABLE
OVERNIGHT TONIGHT.
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
AVIATION.....NF
SHORT TERM...DG
LONG TERM....JB
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page