778
FXUS65 KBOI 130615
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
1215 AM MDT WED MAY 13 2026
UPDATE
UPDATED AVIATION DISCUSSION.
KEY MESSAGES
- RECORD HIGH TEMPERATURES THIS AFTERNOON, WHERE LOW LYING AREAS
WILL SEE HIGHS IN THE 90S.
- A COLD FRONTAL PASSAGE BRINGS VERY GUSTY WINDS, A SLIGHT
CHANCE OF THUNDERSTORMS, AND COOLING CONDITIONS WEDNESDAY.
- JUST ABOVE NORMAL TEMPS THROUGH FRIDAY BEFORE ANOTHER
COOLDOWN THIS WEEKEND, CONDITIONS STAY DRY AND BREEZY.
SHORT TERM /THROUGH FRIDAY NIGHT/
ISSUED 230 PM MDT TUE MAY 12 2026
HIGH PRESSURE OVER THE AREA, AND MOSTLY CLEAR SKIES TODAY WILL
ALLOW TEMPS TO CLIMB THROUGH LATE THIS AFTERNOON. LOW-LYING
AREAS INCLUDING THE SNAKE PLAIN AND VALLEYS IN THE BOISE
MOUNTAINS, WEISER BASIN, AND MALHEUR COUNTY WILL SEE TEMPS IN
THE 90S FOR THEIR AFTERNOON HIGHS. THIS THREATENS DAILY HIGH
TEMP RECORDS FOR MANY LOCATIONS IN SOUTHWEST IDAHO AND SOUTHEAST
OREGON. ALONGSIDE THE HOT TEMPS IS EXCEPTIONAL DRYNESS. THE 18Z
SOUNDING REVEALED A NEARLY DRY ADIABATIC ATMOSPHERE UP TO 500
MB. THERE IS JUST ENOUGH MOISTURE AT THIS LEVEL TO PRODUCE SOME
ALTOCUMULUS, AND WITH VISIBLE VIRGA THERE IS A SLIM CHANCE FOR
STRONG WINDS NEAR THE CLOUDS. RIGHT NOW, THIS SEEMS VERY
UNLIKELY GIVEN THE DEPTH OF THE DRY LAYER AND LIMITED MOISTURE
AVAILABLE TO CONVECTION.
TEMPERATURES COOL QUICKLY AFTER SUNSET AS THE FOCUS SHIFTS TO A
QUICKLY ENCROACHING UPPER LEVEL LOW MOVING INLAND. THIS LOW WILL
CARRY A STRONG COLD FRONT THROUGH MOST OF THE INTERMOUNTAIN
WEST. THE PRIMARY HAZARD FOR OUR AREA AS THIS FRONT MOVES
THROUGH IS THE WINDS. LATE IN THE MORNING THROUGH THE EARLY
EVENING, WIND GUSTS INCREASE TO 40-55 MPH ACROSS OPEN AREAS AND
RIDGES. A WIND ADVISORY HAS BEEN ISSUED IN THE AREAS EXPECTED
TO SEE THE STRONGEST WINDS. OUTSIDE OF THE ADVISORY, WINDS WILL
STILL GUST 30-40 MPH THROUGHOUT THE DAY SAVE FOR A FEW VERY
SHELTERED MOUNTAIN VALLEYS. WINDS WILL KICK UP DUST, ESPECIALLY
ALONG THE FRONT, LEADING TO REDUCED VISIBILITIES. IN THE
MORNING AND EARLY AFTERNOON, AS THE FRONT ITSELF PASSES,
THUNDERSTORMS WILL BE POSSIBLE. GUSTS OUT OF THUNDERSTORMS COULD
LOCALLY ENHANCE THE ALREADY GUSTY CONDITIONS IN PARTS OF THE
UPPER SNAKE PLAIN. THE ENHANCEMENT COULD BRIEFLY TAKE WINDS UP
TO 60 MPH. FORECASTS, HOWEVER, CONTINUE TO FAVOR THUNDERSTORM
DEVELOPMENT OVER THE WEST CENTRAL AND CENTRAL IDAHO MOUNTAINS.
MODERATE RAIN AND SMALL HAIL WILL ALSO BE POSSIBLE IN STORMS.
WINDS FINALLY BEGIN TO WEAKEN AFTER SUNSET, BUT REMAIN ELEVATED
OVERNIGHT. BEHIND THE FRONT, TEMPS ON THURSDAY WILL BE SEASONAL
ACROSS THE AREA. WINDS STAY ELEVATED THROUGH THE DAY, ESPECIALLY
IN CENTRAL AND SOUTH-CENTRAL IDAHO AND CENTRAL OREGON. WHILE
TUESDAY IS THE DRIEST DAY, AFTERNOON MINIMUM RELATIVE HUMIDITIES
REMAIN IN THE TEENS FOR SOUTHERN AREAS EACH DAY. THE COINCIDENCE
OF DRY AIR AND GUSTY WINDS HIGHLIGHTS ELEVATED FIRE WEATHER
CONDITIONS, ESPECIALLY WEDNESDAY.
LONG TERM /SATURDAY THROUGH WEDNESDAY/
ISSUED 230 PM MDT TUE MAY 12 2026
GOOD MODEL AGREEMENT IN THE OVERALL LARGE SCALE PATTERN FRIDAY
THROUGH SUNDAY. DRY WESTERLY FLOW FRIDAY WITH TEMPERATURES AROUND
NORMAL. A SUBSTANTIAL COOL DOWN FOR THE WEEKEND (TEMPERATURES 10
DEGREES BELOW NORMAL) AS A SHORTWAVE TROUGH MOVES ACROSS THE AREA.
NOT A LOT OF MOISTURE EXPECTED WITH THIS SYSTEM SO THERE'S ONLY A
LOW END CHANCE (20-30 PERCENT) OF PRECIPITATION FOR NORTHERN BAKER
COUNTY AND PORTIONS OF THE WEST CENTRAL AND BOISE MOUNTAINS. EXPECT
BREEZY NW WINDS SATURDAY AND SUNDAY AFTERNOON, ESPECIALLY ACROSS
BAKER COUNTY AND THE SNAKE RIVER PLAIN. TEMPERATURES EXPECTED TO
TREND UP WITH DRY CONDITIONS ON MONDAY. FORECAST UNCERTAINTY GROWS
TUESDAY WITH SOME MODEL GUIDANCE SUGGESTING ANOTHER SHORTWAVE TROUGH
WITH LIMITED MOISTURE MAY MOVE ACROSS THE REGION.
AVIATION /06Z WEDNESDAY THROUGH THURSDAY/
ISSUED 1206 AM MDT WED MAY 13 2026
VFR WITH SCATTERED SHOWERS/THUNDERSTORMS AND SOME BRIEF GUSTY
OUTFLOW WINDS OVERNIGHT THROUGH MORNING. A STRONG COLD FRONT
WILL PASS THROUGH THE AREA LATE MORNING/EARLY AFTERNOON,
BRINGING STRONG W-NW WINDS AND SCATTERED SHOWERS/THUNDERSTORMS.
FRONTAL PASSAGE EXPECTED 15-17Z FOR SE OR SITES AND 17-20Z FOR
SW ID SITES. SURFACE WINDS SSW 10-20 KT OVERNIGHT, THEN WNW
20-30 KT WITH HIGHER GUSTS AFTER FRONTAL PASSAGE IN THE
AFTERNOON. STRONGEST WINDS NEAR KMUO, KTWF, AND KJER. PERIODS OF
LLWS POSSIBLE NEAR THE FRONT. WINDS ALOFT AT 10KFT MSL: SSW
20-25 KT.
KBOI...VFR. STRONG COLD FRONTAL PASSAGE THIS AFTERNOON 17Z-19Z,
WITH STRONG WINDS EXPECTED. SURFACE WINDS ESE 8-12 KT
OVERNIGHT THROUGH MORNING, BECOMING WNW 20-25 KT WITH GUSTS TO
35 KT AFTER 17Z.
BOI WATCHES/WARNINGS/ADVISORIES
ID...WIND ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT MDT TONIGHT
FOR IDZ012-014>016-028>030.
OR...WIND ADVISORY FROM 9 AM MDT /8 AM PDT/ THIS MORNING TO
MIDNIGHT MDT /11 PM PDT/ TONIGHT FOR ORZ064.
WIND ADVISORY FROM 9 AM MDT /8 AM PDT/ THIS MORNING TO 6 PM
MDT /5 PM PDT/ THIS EVENING FOR ORZ061-063.
WWW.WEATHER.GOV/BOISE
INTERACT WITH US VIA SOCIAL MEDIA:
WWW.FACEBOOK.COM/NWSBOISE
WWW.X.COM/NWSBOISE
AVIATION.....JY
SHORT TERM...JM
LONG TERM....TL
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