866  
FXUS65 KBOI 131013  
AFDBOI  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOISE ID  
413 AM MDT TUE OCT 13 2026  
   
UPDATE
 
UPDATED AVIATION DISCUSSION.  
 

 
   
KEY MESSAGES
 
 
- UNSETTLED CONDITIONS THROUGH THE AFTERNOON TODAY, WITH SHOWERS  
MAINLY OVER THE LOWER MAGIC VALLEY.  
 
- COLD MORNING TEMPERATURES THIS MORNING AND WEDNESDAY MORNING  
WILL BRING PATCHY FROST AND NEAR-FREEZING CONDITIONS, WITH  
FROST ADVISORIES IN EFFECT FOR THE SNAKE PLAIN VALLEY AREAS.  
 
- WARM AND DRY CONDITIONS WEDNESDAY THROUGH THE WEEKEND.  
TEMPERATURES REACHING UP TO 10 DEGREES ABOVE NORMAL BY  
FRIDAY.  
 

 
   
SHORT TERM /THROUGH THURSDAY NIGHT/
 
 
ISSUED 309 AM MDT TUE OCT 13 2026  
THE CLOSED UPPER LOW HAS MOVED SOUTH OF US INTO THE GREAT  
BASIN, AND WILL SHIFT EASTWARD OUT OF THE REGION TODAY  
(TUESDAY). THE LOW'S REMAINING MOISTURE LOAD WILL CONTINUE SOME  
PRECIPITATION OVER THE LOWER MAGIC VALLEY NEAR THE NV BORDER  
THIS MORNING THROUGH THE AFTERNOON, BEFORE COMPLETELY TAPERING  
OFF BY THE EVENING. SNOW LEVELS IN THE 4500-6000 FT MSL RANGE  
OVER SOUTH-CENTRAL ID WILL CONTINUE SOME LIGHT SNOW SHOWERS OVER  
HIGH TERRAIN AREAS OF THE SOUTHERN HIGHLANDS AND THE OWYHEES.  
LOW NIGHTTIME TEMPERATURES NEAR FREEZING, COUPLED WITH SOME HIGH  
SURFACE MOISTURE, WILL BRING DENSE FROST COVERAGES OVER MOST  
AREAS THIS MORNING AND WEDNESDAY MORNING. AS SUCH, A FROST  
ADVISORY REMAINS IN PLACE OVER THE SNAKE PLAIN THROUGH WEDNESDAY  
LATE MORNING. OTHERWISE, A PACIFIC RIDGE OF HIGH PRESSURE WILL  
QUICKLY BUILD IN BY TONIGHT, BRINGING DAYTIME TEMPERATURES UP TO  
NEAR AND ABOVE NORMAL WITH DRY CONDITIONS AREAWIDE THROUGH  
THURSDAY. WEDNESDAY WILL SEE TEMPERATURES HOVERING SLIGHTLY  
ABOVE NORMAL, MAINLY OVER THE LOWER TREASURE VALLEY AREAS.  
THURSDAY WILL SEE PEAK TEMPERATURES 5 TO 10 DEGREES ABOVE NORMAL  
AS THE PACIFIC HIGH FURTHER AMPLIFIES OVER THE NORTHWEST  
REGION.  
 

 
   
LONG TERM /FRIDAY THROUGH TUESDAY/
 
 
ISSUED 309 AM MDT TUE OCT 13 2026  
FRIDAY THROUGH SATURDAY WILL CONTINUE TO SEE DRY CONDITIONS AND  
TEMPERATURES 5 TO 10 DEGREES ABOVE NORMAL AS THE LARGE PACIFIC  
HIGH CONTINUES TO BUILD IN AND AMPLIFY OVER THE REGION. CLEAR  
SKIES AND GOOD RADIATIONAL COOLING OVERNIGHT WILL ALLOW FOR  
MOUNTAIN VALLEY FOG DEVELOPMENT THROUGH THE MORNINGS. ON SUNDAY,  
A WEAK SHORTWAVE TROUGH WILL PASS OVER THE NORTHWEST AND BRING  
A DRY COLD FRONT ACROSS OUR AREA. THIS FRONTAL PASSAGE MAY BRING  
A SLIGHT COOLDOWN SUNDAY THROUGH MONDAY. FOR NOW, TEMPERATURES  
ARE STILL LOOKING TO BE 5 TO 10 DEGREES ABOVE NORMAL ON THOSE  
DAYS. ENSEMBLE GUIDANCE REMAINS IN STRONG AGREEMENT ON ANOTHER  
CLOSED UPPER LOW DIGGING INTO THE REGION FROM THE GULF OF ALASKA  
LATE MONDAY THROUGH MIDWEEK. ALTHOUGH SLIGHT UNCERTAINTY  
REMAINS OVER THE INTENSITY AND COVERAGE, MOST AREAS SHOULD SEE  
SOME MODERATE CHANCES OF PRECIPITATION LATE MONDAY THROUGH  
TUESDAY.  
 

 
   
AVIATION /12Z TUESDAY THROUGH WEDNESDAY/
 
 
ISSUED 411 AM MDT TUE OCT 13 2026  
GENERALLY VFR. SCATTERED RAIN SHOWERS AND LOW CLOUDS WILL BRING  
INTERMITTENT MVFR CEILINGS TO THE MAGIC VALLEY THIS MORNING THROUGH  
THE EARLY AFTERNOON. PATCHY VALLEY FOG IN CENTRAL ID MOUNTAINS  
BRINGING BRIEF MVFR/IFR CONDITIONS. MOUNTAINS OBSCURED IN LOW CLOUDS  
AND PRECIPITATION WITH SNOW LEVELS AROUND 4500-5500 FT MSL.  
WIDESPREAD CLEARING IN THE EVENING. SURFACE WINDS: W-NW 5-15 KT WITH  
GUSTS 20-25 KT MAINLY OVER SNAKE PLAIN THIS AFTERNOON THROUGH  
EVENING. WINDS ALOFT AT 10KFT MSL: N-NE 10-20 KT BECOMING N 20-30 KT  
BY TUES/12Z.  
 
KBOI...VFR WITH CLEARING SKIES TODAY THROUGH WEDNESDAY. SURFACE  
WINDS: NW 8-15 KT WITH GUSTS UP TO 20 KT IN THE AFTERNOON, BECOMING  
VARIABLE LESS THAN 6 KT IN THE EVENING.  
 

 
   
BOI WATCHES/WARNINGS/ADVISORIES
 
 
ID...FROST ADVISORY UNTIL 10 AM MDT WEDNESDAY FOR IDZ012-014-016.  
OR...FROST ADVISORY UNTIL 10 AM MDT /9 AM PDT/ WEDNESDAY FOR ORZ064.  

 
 

 
 
WWW.WEATHER.GOV/BOISE  
 
INTERACT WITH US VIA SOCIAL MEDIA:  
WWW.FACEBOOK.COM/NWSBOISE  
WWW.X.COM/NWSBOISE  
 
AVIATION.....JY  
SHORT TERM...JY  
LONG TERM....JY  
 
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