947
FXUS65 KBOI 141720
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
1020 AM MST WED JAN 14 2026
DISCUSSION
A RIDGE REMAINS OVER THE AREA WITH STAGNANT
CONDITIONS AND A TEMPERATURE INVERSION. PATCHY FOG REMAINS
ALONG THE SNAKE RIVER THIS MORNING AND IN THE LONG VALLEY. FOG
IS EXPECTED TO DISSIPATE BRIEFLY THIS AFTERNOON BEFORE
REDEVELOPING AFTER SUNSET AND SLOWLY EXPANDING TONIGHT INTO
THURSDAY MORNING. THE RIDGE WILL EXPAND OVER WESTERN BC OVER THE
NEXT SEVERAL DAYS ALLOWING FOR COOLER AIR TO MOVE INTO THE AREA
FROM THE NORTH AND EAST. FORECAST ON TRACK WITH NO UPDATES.
AVIATION
VFR IN THE MAGIC VALLEY AND NEAR KBNO, ELSEWHERE
MVFR-LIFR CONDITIONS AND MOUNTAIN OBSCURATION IN AREAS OF
FOG/LOW STRATUS THROUGH THE EARLY AFTERNOON, MAINLY IN SHELTERED
MOUNTAIN-VALLEYS AND LOWER BASINS. SURFACE WINDS: VARIABLE UP
TO 10 KT. WINDS ALOFT AT 10KFT MSL: NW 5-20 KT.
KBOI...VFR. MVFR-IFR CONDITIONS ARE POSSIBLE (30% CHANCE) AGAIN
WEDNESDAY NIGHT INTO THURSDAY MORNING FROM FOG AND LOW CEILINGS,
PARTICULARLY AFTER 03Z/THU. SURFACE WINDS: LIGHT AND VARIABLE.
PREV DISCUSSION
SHORT TERM...TODAY THROUGH FRIDAY NIGHT...THE RIDGE OF HIGH
PRESSURE WILL CONTINUE TO EXPAND INTO BRITISH COLUMBIA EACH DAY
THROUGH THE SHORT TERM PERIOD. STABLE CONDITIONS WITH VALLEY FOG
AND STAGNANT AIR IS ANTICIPATED EACH DAY. TEMPERATURES WILL
REMAIN SIMILAR THROUGH THE WEEK, WITH A SLIGHT COOLING TREND IN
THE VALLEYS THANKS TO LINGERING COLD POOLS.
VALLEY FOG REMAINS FICKLE TO FORECAST, WITH HI-RES MODELS
EXPANDING COVERAGE INTO THE LOWER TREASURE VALLEY THROUGH THE
OVERNIGHT AND EARLY MORNING HOURS. THE CURRENT FORECAST KEEPS
VISIBILITY AROUND 1-3 MILES WITH PATCHY COVERAGE, BUT THERE IS A
SIGNIFICANT POTENTIAL FOR THAT TO REDUCE SUBSTANTIALLY AS WE
GET CLOSER TO SUNRISE, SO HAVE KEPT THE DENSE FOG ADVISORY IN
PLACE THROUGH THE MORNING. THE DENSE FOG WILL REMAIN GENERALLY
NEAR THE OWYHEE FOOTHILLS AND ALONG THE SNAKE RIVER NEAR
ONTARIO-WEISER. FOG WILL INCREASE IN COVERAGE IN SHELTERED
VALLEYS EACH NIGHT AS WE CONTINUE TO SEE STABLE CONDITIONS.
LONG TERM...SATURDAY THROUGH WEDNESDAY...STABLE CONDITIONS
(THANKS TO THIS RIDGE STAYING WELL PAST IT'S WELCOME) WILL
CONTINUE THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. EXPECT MORE
OF THE SAME UNDER THIS PATTERN...WARM MID SLOPES AND RIDGETOPS
WITH COLD VALLEY TEMPERATURES AND STAGNANT CONDITIONS WITH
VALLEY FOG THROUGH NEXT TUESDAY. BY THE MIDDLE OF NEXT WEEK,
MODELS STILL HINT AT AN INCOMING SHORTWAVE TROUGH BRINGING
PRECIPITATION AND COLDER AIR WITH BREEZY WINDS, WHICH WOULD
HOPEFULLY BE ENOUGH TO SCOUR OUT THIS INVERSION. UNCERTAINTY
REMAINS IN THE STRENGTH OF THIS TROUGH, BUT AGREEMENT IS HIGH IN
THE RIDGE BREAKING DOWN BY THE END OF NEXT WEEK.
BOI WATCHES/WARNINGS/ADVISORIES
ID...AIR STAGNATION ADVISORY UNTIL 5 AM MST MONDAY
IDZ011>014-016-028-033.
DENSE FOG ADVISORY UNTIL NOON MST TODAY IDZ012.
OR...AIR STAGNATION ADVISORY UNTIL 5 AM MST /4 AM PST/ MONDAY
ORZ061>064.
DENSE FOG ADVISORY UNTIL NOON MST /11 AM PST/ TODAY ORZ064.
WWW.WEATHER.GOV/BOISE
INTERACT WITH US VIA SOCIAL MEDIA:
WWW.FACEBOOK.COM/NWSBOISE
WWW.X.COM/NWSBOISE
DISCUSSION...KA
AVIATION.....CH
SHORT TERM...SA
LONG TERM....SA
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