136
FXUS65 KBOI 171206
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
606 AM MDT WED JUN 17 2026
UPDATE
UPDATED AVIATION DISCUSSION.
KEY MESSAGES
- GUSTY WINDS AND VERY DRY CONDITIONS TODAY.
- A CHANCE OF SHOWERS AND THUNDERSTORMS RETURNS TO THE AREA
FRIDAY AND SATURDAY. STORMS COULD PRODUCE STRONG OUTFLOW WINDS
AND HEAVY RAIN.
SHORT TERM /THROUGH FRIDAY NIGHT/
ISSUED 311 AM MDT WED JUN 17 2026
AN UPPER LEVEL TROUGH SHIFTING EASTWARD ACROSS THE PACIFIC
NORTHWEST TODAY WILL TIGHTEN PRESSURE GRADIENTS ACROSS SOUTHEAST
OREGON AND SOUTHWEST IDAHO. THIS WILL RESULT IN BREEZY WEST TO
NORTHWEST WINDS OF 15 TO 25 MPH, WITH LOCAL GUSTS UP TO 35 MPH,
ESPECIALLY ACROSS THE WESTERN SNAKE RIVER PLAIN AND HIGHER
TERRAIN. COMBINED WITH MINIMUM RELATIVE HUMIDITY VALUES DROPPING
INTO THE 10 TO 15 PERCENT RANGE FOR LOWER ELEVATIONS, ELEVATED
FIRE WEATHER CONDITIONS ARE EXPECTED AGAIN TODAY PROMPTING THE
RED FLAG WARNING. TEMPERATURES WILL BE ABOUT 5 TO 7 DEGREES
COOLER TODAY FROM YESTERDAY.
WINDS WILL DECOUPLE TONIGHT AS A WEAK TRANSITORY RIDGE BUILDS
INTO THE REGION. THURSDAY LOOKS TO BE A QUIETER, WARMER DAY
UNDER THE INFLUENCE OF THIS RIDGE. TEMPERATURES WILL BE IN THE
UPPER 80S TO LOW 90S ACROSS THE LOWER VALLEYS THURSDAY. RELATIVE
HUMIDITY VALUES WILL REMAIN QUITE LOW ON THURSDAY, BUT LIGHT
TERRAIN DRIVEN WINDS WILL LIMIT THE OVERALL FIRE WEATHER THREAT
COMPARED TO TODAY.
MORE ACTIVE WEATHER IS EXPECTED ON FRIDAY WITH AN INCOMING LOW
PRESSURE SYSTEM MOVING ONSHORE OVER NORTHERN CALIFORNIA. THIS
SYSTEM WILL BRING AN INFLUX OF MID LEVEL MOISTURE AND
INSTABILITY INTO SOUTHEAST OREGON AND SOUTHWEST IDAHO. MODEL
GUIDANCE CONTINUES TO SIGNAL A DISTINCT THREAT FOR THUNDERSTORM
DEVELOPMENT STARTING FRIDAY AFTERNOON AND EVENING. GIVEN INITIAL
LOW LEVELS REMAINING RELATIVELY DRY, THESE STORMS WILL CARRY A
RISK OF DRY LIGHTNING AND STRONG, ERRATIC OUTFLOW WINDS,
INCREASING FIRE IGNITION POTENTIAL. WIND GUSTS OF 50 TO 60 MPH
WITH BLOWING DUST IS POSSIBLE (10% CHANCE) ESPECIALLY ACROSS
SOUTHEAST OREGON. THE RIDGE WILL REACH PEAK AMPLITUDE OVER
SOUTHERN IDAHO FRIDAY IN RESPONSE TO THE APPROACHING TROUGH
BRINGING TEMPERATURES BACK INTO THE MID 90S ACROSS THE LOWER
VALLEYS.
LONG TERM /SATURDAY THROUGH WEDNESDAY/
ISSUED 311 AM MDT WED JUN 17 2026
AS THE CORE OF THE LOW MOVES CLOSER ON SATURDAY, MOISTURE
PROFILES DEEPEN SIGNIFICANTLY, BRINGING A MIX OF WET AND DRY
THUNDERSTORMS AND INCREASING THE THREAT FOR HEAVY RAIN AND FLASH
FLOODING ON BURN SCARS. THE BEST CHANCE FOR THUNDERSTORMS (30
TO 60%) LOOKS TO BE ACROSS THE HIGHER TERRAIN OF SOUTHWEST
IDAHO. WITH PRECIPITABLE WATER APPROACHING THE 80TH TO 90TH
PERCENTILE, THE STRONGEST STORMS COULD PRODUCE HEAVY RAIN IN
ADDITION TO SMALL HAIL AND GUSTY WINDS. BURN SCARS, LIKE THE
WAPITI BURN SCAR, WILL NEED TO BE MONITORED FOR FLASH FLOOD
POTENTIAL.
COOLER AIR ACCOMPANYING THE SYSTEM WILL KNOCK TEMPERATURES DOWN
BY SUNDAY, RETURNING HIGHS CLOSER TO SEASONAL NORMALS. HIGH
PRESSURE BUILDS BACK OVER THE REGION EARLY NEXT WEEK, LEADING TO
A RETURN OF DRY CONDITIONS AND A STEADY WARMING TREND THROUGH
WEDNESDAY. THE UPPER LEVEL FLOW REMAINS ACTIVE AND THUS THE
WARMING LOOKS TO BE SHORT LIVED.
AVIATION /12Z WEDNESDAY THROUGH THURSDAY/
ISSUED 604 AM MDT WED JUN 17 2026
VFR. SURFACE WINDS: W-NW 5-15 KT THIS MORNING. W-NW 10-20 KT,
GUSTS 25-35 KT FROM KMUO TO KTWF/KJER, AND ALSO NEAR KBKE THIS
AFTERNOON. WINDS ALOFT AT 10KFT MSL: NW 25-40 KT.
KBOI...VFR. SURFACE WINDS: NW 10-20 KT.
BOI WATCHES/WARNINGS/ADVISORIES
ID...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR
IDZ424-426.
OR...NONE.
WWW.WEATHER.GOV/BOISE
INTERACT WITH US VIA SOCIAL MEDIA:
WWW.FACEBOOK.COM/NWSBOISE
WWW.X.COM/NWSBOISE
AVIATION.....JDS
SHORT TERM...JDS
LONG TERM....JDS
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page