293
FXUS65 KBOI 182105
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
205 PM MST WED FEB 18 2026
SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
SCATTERED SNOW
SHOWERS WILL DECREASE IN COVERAGE LATER THIS AFTERNOON AS THE
CORE OF THE UPPER TROUGH MOVES EAST. HOWEVER, LINGERING
MOISTURE AND COLD AIR ALOFT WILL MAINTAIN A SLIGHT CHANCE OF
LIGHT SNOW IN THE MOUNTAINS THROUGH THE OVERNIGHT HOURS. SNOW
IN THE VALLEYS WILL HAVE TIME TO MOSTLY MELT BEFORE SUNSET,
LEADING TO INCREASED BOUNDARY LAYER MOISTURE FOR PATCHY FOG
DEVELOPMENT OVERNIGHT. THE TREASURE VALLEY WILL HAVE THE BEST
CHANCE FOR FOG TONIGHT. LOW TEMPERATURES IN THE MOUNTAINS WILL
REACH BETWEEN -10 TO 15 DEGREES WITH THE VALLEYS SEEING MOSTLY
20S ACROSS THE REGION.
THE REGION REMAINS UNDER THE INFLUENCE OF A BROAD, COOL TROUGH
THROUGH FRIDAY. ANOTHER WEAK SHORTWAVE WILL CLIP THE AREA ON
THURSDAY, PRIMARILY IMPACTING SOUTHEAST OREGON AND THE CENTRAL
IDAHO MOUNTAINS. THIS WILL TRIGGER ANOTHER ROUND OF CONVECTIVE
SNOW SHOWERS DURING THE AFTERNOON WITH MINIMAL ACCUMULATIONS OF
1 TO 2 INCHES IN HIGHER TERRAIN. LOWER VALLEYS MAY SEE A FEW
LIGHT FLAKES OR A BRIEF RAIN AND SNOW MIX, BUT LITTLE TO NO
ACCUMULATION IS EXPECTED AS TEMPERATURES RISE INTO THE LOW 40S.
BY FRIDAY, THE TROUGH BEGINS TO SHIFT FURTHER EAST AND HEIGHTS
START TO RISE. WHILE A FEW STRAY SHOWERS REMAIN POSSIBLE OVER
THE HIGHER PEAKS OF THE WEST CENTRAL AND BOISE MOUNTAINS, MOST
AREAS WILL SEE A DRYING TREND. TEMPERATURES WILL REMAIN 5 TO 10
DEGREES BELOW NORMAL THROUGH FRIDAY NIGHT, WITH CLEARING SKIES
ALLOWING FOR CHILLY OVERNIGHT LOWS.
LONG TERM...SATURDAY THROUGH WEDNESDAY
HIGH PRESSURE BUILDS
OVER THE AREA THIS WEEKEND AS A DEEP LOW DEVELOPS OFF THE
PACIFIC NORTHWEST COAST. THE HIGH PRESSURE WILL KEEP CONDITIONS
DRY WITH A WARMING TREND. THE LOW OFF THE COAST WILL STRENGTHEN
THE PRESSURE GRADIENT IN THE SOUTHWEST FLOW AS IT APPROACHES ON
MONDAY, LEADING TO MONDAY BEING THE WARMEST DAY IN THE FORECAST
JUST BEFORE THE LOW SWITCHES THE PATTERN. TEMPS RISE FROM NEAR
NORMAL ON SATURDAY TO 5 DEGREES ABOVE NORMAL ON MONDAY. A 10-20%
CHANCE OF PRECIP SUNDAY EVENING IN THE FAR WESTERN FRINGE OF
OUR AREA TURNS INTO A 50-80% CHANCE OF PRECIP (LOWER IN VALLEYS,
HIGHER IN MOUNTAINS) ON MONDAY EVENING. THIS HAPPENS AS THE LOW
REJOINS THE PRIMARY JET STREAM AND CARRIES MOISTURE AND
FAVORABLE DYNAMICS FOR PRECIPITATION THROUGH THE AREA. AS IT
REJOINS, THE FLOW BECOMES ZONAL AND HEIGHTS DROP, LEADING TO A
SLIGHT REDUCTION IN TEMPS DOWN TO NORMAL, WITH SNOW LEVELS NEAR
4-5 KFT MSL BY TUESDAY, AND DOWN FURTHER TO 3-4 KFT MSL BY
WEDNESDAY. THE PRECIPITATION CONTINUES FROM MONDAY EVENING
THROUGH WEDNESDAY MORNING, BEFORE ANOTHER LOW OFF THE PACIFIC
NORTHWEST COAST STALLS AND A WEAK RIDGE REBUILDS OVER THE
REGION. THE FLOW IS LOOKING TO REMAIN MOIST, BUT TEMPS WILL STAY
SEASONAL.
AVIATION
SCATTERED SNOW SHOWERS BRINGING IFR-LIFR CONDITIONS ARE
CLEARING TO THE SOUTHEAST THIS AFTERNOON, GIVING WAY TO VFR WITH MID-
LEVEL CEILINGS. POOR CONDITIONS CONTINUE IN THE MOUNTAINS THROUGH
THE DAY AS ISOLATED SHOWERS CONTINUE. PRECIPITATION TODAY WILL
INCREASE THE CHANCES FOR FOG DEVELOPMENT TONIGHT, WITH A 30% CHANCE
OF FORMATION IN THE LOWER SNAKE PLAIN AND MOUNTAIN VALLEYS. SURFACE
WINDS: W-NW 10-15 KT, WITH GUSTS UP TO 30 KT THROUGH THE AFTERNOON.
WINDS ALOFT AT 10KFT MSL: W-NW 10-20 KT.
KBOI...SNOW SHOWERS ARE TAPERING OFF IN THE REGION, GIVING WAY TO
VFR CONDITIONS FOR THE LATE AFTERNOON AND EVENING. TONIGHT, THERE IS
A 30% CHANCE FOR FOG TO FORM. SURFACE WINDS: NW 10-15 KT WITH GUSTS
UP TO 25 KT, BECOMING LIGHT AND VARIABLE THIS EVENING AND
TONIGHT.
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...JDS
LONG TERM....JM
AVIATION.....JM
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