632  
FXUS65 KBOI 172005  
AFDBOI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOISE ID  
205 PM MDT MON AUG 17 2026  
   
KEY MESSAGES  
 
- ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON OVER HIGHER  
TERRAIN, WITH GUSTY OUTFLOWS UP TO 35 MPH.  
 
- TEMPERATURES NEAR OR SLIGHTLY ABOVE NORMAL THROUGH MID-WEEK,  
THEN HEAT AMPLIFYING FOR THURSDAY AND FRIDAY.  
 
- RETURN OF MONSOON MOISTURE FRIDAY INTO THE WEEKEND WILL  
INCREASE SHOWER AND THUNDERSTORM CHANCES ONCE AGAIN.  
 
 
   
SHORT TERM /THROUGH WEDNESDAY NIGHT/  
 
A DISTINCT LINE OF VERY LIGHT SHOWERS IS CURRENTLY PUSHING NORTH  
OVER THE TREASURE VALLEY AND MALHEUR COUNTY, WITH MINIMAL  
PRECIPITATION AMOUNTS OBSERVED AS OF 2PM MDT. CLOUD COVER WILL  
CONTINUE TO PERSIST THROUGH THE EVENING, WITH A WEAK SHORTWAVE  
TROUGH MOVING THROUGH THE REGION THIS AFTERNOON. THIS WILL  
CONTINUE THE 10-20% CHANCE OF SHOWERS AND THUNDERSTORMS,  
PRIMARILY OVER THE CENTRAL ID MOUNTAINS AND NEAR THE HIGH  
TERRAIN OVER THE NV-ID BORDER. THE PRIMARY HAZARDS WITH ANY OF  
THESE THUNDERSTORMS WILL BE GUSTY OUTFLOWS UP TO 35 MPH AND  
LIGHTNING. THUNDERSTORM POTENTIAL IS SLIGHTLY LOWER THAN  
PREVIOUSLY FORECAST DUE TO THE WIDESPREAD PERSISTENT CLOUD  
CLOVER THIS AFTERNOON. LINGERING MOISTURE OVER EASTERN VALLEY  
COUNTY TOMORROW WILL KEEP A 5-10% CHANCE OF SHOWERS AND  
THUNDERSTORMS THROUGH THE EVENING. HIGH PRESSURE WILL BUILD  
BACK IN OVER THE INTERMOUNTAIN WEST TOMORROW THROUGH THE END OF  
THE SHORT TERM PERIOD, BRINGING A STEADY WARMING AND DRYING  
TREND WITH GENERALLY LIGHT WINDS. SMOKE FROM OREGON/WASHINGTON  
WILDFIRES WILL FILTER INTO THE REGION TOMORROW, WITH THE  
THICKEST SMOKE OVER BAKER COUNTY, OR.  
 
 
   
LONG TERM /THURSDAY THROUGH MONDAY/  
 
THE FOUR CORNERS UPPER-LEVEL RIDGE WILL CONTINUE TO BUILD THURSDAY  
AND FRIDAY WITH THE PACIFIC LOW PRESSURE SYSTEM SLOWLY MOVING  
TOWARDS THE SHORE. SOUTHWESTERLY FLOW ALOFT WILL TRANSITION TO  
INCREASED SOUTHERLY WINDS THROUGH MUCH OF THE WEEKEND. THIS PATTERN  
WILL BRING BACK SUMMERTIME HEAT RISK, WITH TEMPERATURES CLIMBING TO  
NEAR 100 DEGREES FOR LOWER ELEVATIONS. PRECIPITATION CHANCES WILL  
START ISOLATED IN THE HIGHER TERRAIN OF SW IDAHO THURSDAY,  
INCREASING TO MOST HIGHER ELEVATIONS ACROSS SW IDAHO AND SE OREGON  
FRIDAY. AFTERNOON WIND GUSTS WILL ALSO BECOME BREEZIER LATE WEEK  
INTO THE WEEKEND. THE UPPER-LEVEL TROUGH WILL MOVE ONSHORE LATE  
FRIDAY INTO SATURDAY AND QUICKLY MOVE NE THROUGH THE PACIFIC NW AND  
NORTHERN ROCKIES. COOLING TEMPERATURES TO NEAR-NORMAL ARE FORECAST  
SATURDAY AND SUNDAY WITH THIS DISTURBANCE MOVING THROUGH.  
 
 
   
AVIATION /18Z MONDAY THROUGH TUESDAY/  
 
ISSUED 1120 AM MDT MON AUG 17 2026  
 
VFR. WEAK, ISOLATED SHOWERS AND THUNDERSTORMS THIS  
AFTERNOON/EVENING ACROSS NE OREGON AND S-CENTRAL/CENTRAL IDAHO,  
INCLUDING KTWF-KJER. ERRATIC OUTFLOWS TO AROUND 35 KT POSSIBLE.  
PATCHY SURFACE SMOKE NEAR KBKE/KBNO. SURFACE WINDS: VARIABLE UP  
TO 10 KT, BECOMING SW-NW 5-15 KT THIS AFTERNOON. WINDS ALOFT AT  
10KFT MSL: SW 5-15 KT, BECOMING W 5-15 BY 00Z/TUESDAY.  
 
KBOI...VFR. WEAK, ISOLATED SHOWERS AND THUNDERSTORMS IN SW  
IDAHO THIS PM, WITH A 10% CHANCE OF IMPACTING KBOI. POSSIBLE  
STORM OUTFLOWS AROUND 20-30 KT IN TREASURE VALLEY. SURFACE  
WINDS: VARIABLE OR SE AROUND 6 KT, SHIFTING TO NW-N 5-10 KT IN  
THE AFTERNOON.  
 
 
   
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  
 
SHORT TERM...SA  
LONG TERM....CH  
AVIATION.....CH  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab ID Page
The Nexlab OR Page
Main Text Page