170
FXUS65 KBOI 241544
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
944 AM MDT THU APR 24 2025
DISCUSSION
A WEAK RIDGE ACROSS THE AREA TODAY WILL MAKE FOR
MOSTLY CLEAR SKIES AND ABOVE AVERAGE TEMPERATURES. THIS IS IN
RESPONSE TO A DEVELOPING UPPER LEVEL LOW PRESSURE SYSTEM OFF THE
CALIFORNIA COAST. THERE REMAINS ENOUGH MOISTURE AND INSTABILITY
ACROSS CENTRAL IDAHO THIS AFTERNOON FOR A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS.
MORE ACTIVE WEATHER IS EXPECTED ON FRIDAY AS MOISTURE AND
DYNAMICS INCREASE ACROSS THE FORECAST AREA AHEAD OF THE CLOSED
LOW. CLOUDS AND SHOWERS WILL BE A LIMITING FACTOR FRIDAY
AFTERNOON HOWEVER, HIGH-RES MODELS REMAIN CONSISTENT IN CLEARING
ACROSS MUCH OF THE SOUTHWEST IDAHO FRIDAY AFTERNOON. SURFACE
HEATING SHOULD BOOST SBCAPE VALUES UP TO 600 J/KG WITH SHEAR
AROUND 30 KTS ALONG THE IDAHO/NEVADA BORDER. THIS WILL SHOULD
BE MORE THAN SUFFICIENT TO SUPPORT LONG-LIVED THUNDERSTORMS
DEVELOPMENT. THESE STORMS WILL MOVE NORTHWARD INTO THE SNAKE
RIVER PLAIN AND CENTRAL IDAHO MOUNTAINS LATE FRIDAY AFTERNOON
AND EVENING. NO UPDATES NEEDED AT THIS TIME.
AVIATION
VFR. CHANCE OF SHOWERS AND SLIGHT CHANCE (10-20%) OF
THUNDER IN THE AFTERNOON OVER THE WEST-CENTRAL & BOISE MTNS AND NEAR
KYML. SURFACE WINDS: VARIABLE 5-15 KT, THEN E-SE 5-15 KT THROUGH
EVENING/OVERNIGHT. WINDS ALOFT AT 10KFT: VARIABLE 5-15 BECOMING S-SW
10-20 KT TONIGHT.
KBOI... VFR. VARIABLE UNDER 5 KT THIS MORNING BECOMING NW UP TO
10 KT MIDDAY AND AFTERNOON. SHIFTING TO E-SE UNDER 10 KT
THROUGH EVENING/ OVERNIGHT.
WEEKEND OUTLOOK... VFR. ACTIVE WEATHER THROUGH THE WEEKEND, WITH
CHANCES OF SHOWERS AND SLIGHT CHANCES OF AFTERNOON THUNDERSTORMS
THROUGHOUT THE AREA FRIDAY-SUNDAY. SHOWERS/THUNDERSTORMS MAY RESULT
IN AREAS OF MVFR, MOUNTAIN OBSCURATION, AND PRODUCE GUSTY OUTFLOWS.
WINDS INCREASING THROUGH SUNDAY, WITH GUSTS UP TO 30 KT SUNDAY
AFTERNOON.
PREV DISCUSSION
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...A WEAK UPPER LEVEL
LOW WILL MOVE THROUGH THE CWA TODAY, PROVIDING CONDITIONS FOR
SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS IN THE NORTHEAST
PORTION OF THE AREA (MAINLY IN VALLEY COUNTY SOUTHEAST INTO THE
CAMAS PRAIRIE). AS A DEEP LOW MOVES SOUTH ALONG THE COAST, OUR
UPPER FLOW WILL BECOME SSW TONIGHT, THEN SSE TO SE FRIDAY
THROUGH SATURDAY NIGHT. SHOWERS AND THUNDERSTORMS ASSOCIATED
WITH THIS LOW WILL MOVE INTO MOST OF THE AREA FROM THE
SOUTHWEST FRIDAY AND LINGER THROUGH SATURDAY NIGHT. THE CHANCE
OF MEASURABLE PRECIPITATION IN ANY ONE SPOT VARIES OVER A
CONSIDERABLE RANGE, BUT IS GENERALLY HIGHEST IN THE AFTERNOONS
AND EVENINGS, AS IS USUALLY THE CASE. BECAUSE THE LOW WILL BE TO
OUR SOUTH, THE HIGHEST CHANCE OF PRECIPITATION IS ALSO OVER
ROUGHLY THE SOUTHERN HALF OF THE CWA, WHICH IS ROUGHLY SOUTH OF
ONTARIO. TEMPERATURES WILL AROUND 5 DEGREES ABOVE NORMAL TODAY,
THEN WARM A FEW MORE DEGREES AS WARM SOUTHERLY FLOW ARRIVES
FRIDAY AND SATURDAY. WINDS ARE EXPECTED TO BE LESS THAN 10 MPH
IN MOST AREAS TODAY, BUT GUSTY EAST TO SOUTHEAST WINDS SOUTHEAST
OF MOUNTAIN HOME WILL DEVELOP FRIDAY.
LONG TERM...SUNDAY THROUGH THURSDAY...SHOWERS SUNDAY AS AN UPPER
CLOSED LOW MAKES ITS WAY ACROSS THE GREAT BASIN. CURRENT ENSEMBLES
SHOW A GOOD SIGNAL FOR INSTABILITY. THIS IS ALLOWING A SLIGHT CHANCE
(10-20%) OF THUNDERSTORMS NEARLY AREA WIDE SUNDAY AFTERNOON, WITH
THE EXCEPTION OF HARNEY AND WESTERN BAKER COUNTIES. CHANCES OF
PRECIPITATION SUNDAY EVENING RANGE FROM 20-80%, GENERALLY INCREASING
AS YOU MOVE EAST AND IN HIGHER ELEVATIONS. WE BEGIN TO DRY OUT AREA
WIDE THROUGH MONDAY MORNING AS THE CLOSED LOW MOVES OFF TO OUR EAST
ALLOWS FOR RIDGING TO BUILD IN BEHIND IT. BREEZY NORTHWEST
WINDS PERSIST SUNDAY THROUGH MONDAY AS THE LOW VACATES OUR AREA.
PRECIPITATION CHANCES RETURN TO HIGHER ELEVATIONS TUESDAY
AFTERNOON THROUGH WEDNESDAY AFTERNOON, AS ANOTHER (WEAKER)
TROUGH CROSSES OVER OUR AREA. THE PRECIPITATION CHANCES IN
HIGHER ELEVATIONS RANGE FROM 20-50%. DRY AREA WIDE THURSDAY AS
RIDGING BUILDS IN.
TEMPERATURES FOLLOW A WARMING TREND SUNDAY THROUGH THURSDAY,
STARTING RIGHT AROUND NORMAL BEFORE WARMING UP TO 5-10 DEGREES ABOVE
NORMAL BY THURSDAY. SNOW LEVELS FOLLOW SUIT, RISING FROM 6-7 KFT ON
SUNDAY TO 8-9 KFT COME THURSDAY. SNOW ACCUMULATIONS WILL BE MINIMAL
AND CONFINED TO THE HIGHEST ELEVATIONS SUNDAY THROUGH THURSDAY.
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
DISCUSSION...JDS
AVIATION.....JY
SHORT TERM...SP
LONG TERM....NF
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