120
FXUS65 KPIH 211813
AFDPIH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
1213 PM MDT THU MAY 21 2026
KEY MESSAGES
- SHOWERS AND ISOLATED THUNDERSTORMS SHOULD END BY EARLY EVENING
- GUSTY NORTHERLY WINDS EXPECTED THROUGH THIS EVENING
- MUCH WARMER AND MOSTLY DRY WEATHER FOR MEMORIAL DAY WEEKEND
UPDATE
ISSUED AT 551 AM MDT THU MAY 21 2026
WINDS ARE ALREADY PUSHING THE THRESHOLD FOR A NORTHEAST WIND
LAKE WIND ADVISORY. WITH SHOWERS AND STORMS THIS MORNING, WE
COULD SEE EVEN HIGHER GUSTS ON THE RESERVOIR. WE WENT AHEAD AND
STARTED THE LAKE WIND ADVISORY EFFECTIVE IMMEDIATELY NOW THAT
THE SUN IS COMING UP.
DISCUSSION
ISSUED AT 1225 AM MDT THU MAY 21 2026
LOW PRESSURE WILL CONTINUE TO SLIDE SOUTHEAST TODAY AND PUSH A
COLD FRONT THROUGH EASTERN IDAHO. FOR MOST AREAS, LIGHT AMOUNTS
OF MOISTURE ARE EXPECTED. FOR AREAS ALONG THE MONTANA BORDER
DOWN THROUGH THE BIG HOLES COULD PICK UP AROUND 0.25",
ESPECIALLY WITH ANY HEAVIER SHOWERS OR STORMS THAT CAN OVERCOME
DRIER AIR IN PLACE. OTHERWISE, LIGHT AMOUNTS OF PRECIPITATION
(INCLUDING LIGHT AMOUNTS OF SNOW ON HIGHER RIDGELINES AND
PEAKS). WITH THE COLD FRONT DROPPING SOUTH INTO OUR AREA TODAY,
GUSTY NORTHERLY WINDS ARE EXPECTED. THE FRONT APPEARS TO HANG UP
OVER THE MAGIC VALLEY AND SURROUNDING AREAS FOR A FEW HOURS
THIS AFTERNOON. THIS MAY CAUSE A FEW SHOWERS ACROSS THE LOWER
SNAKE PLAIN OUT INTO THE MAGIC VALLEY TO STICK AROUND THIS
AFTERNOON, AS THE BULK OF THE MOISTURE SHIFTS INTO WYOMING.
WINDS WILL BE STRONG ENOUGH TO MEET THE LOWER SPEED THRESHOLDS
FOR A NORTHEAST LAKE WIND ADVISORY ON AMERICAN FALLS RESERVOIR
THROUGH MOST OF THE DAY. DESPITE SOME CLOUDS OVER CENTRAL AND
EASTERN IDAHO TONIGHT, WE SHOULD MORE CONCERNS WITH FROST AND
FREEZE CONDITIONS. A FROST ADVISORY WILL BE NEEDED FOR THE SNAKE
PLAIN AS TEMPERATURES WILL BE MOSTLY IN 32-36 RANGE, WITH MORE
RURAL AREAS POSSIBLY DROPPING TO AROUND 30 AND ABOVE 36 ALONG
THE I-15 CORRIDOR.
FOR FRIDAY THROUGH MONDAY, TEMPERATURES WILL BE QUICKLY
REBOUNDING WITH HIGHS IN THE 70S AND 80S FOR MEMORIAL DAY
WEEKEND. THE CONCERN IS THAT WE MAY NOT BE TOTALLY SHOWER OR
THUNDERSTORM FREE. WE ARE SEEING SOME POTENTIAL FOR MID LEVEL
CLOUD COVER TO CROSS THE STATE FROM TIME TO TIME, BUT IT MAY NOT
BE ANYTHING MORE THAN VIRGA OR SPRINKLES. RIGHT NOW, ANY GIVEN
DAY'S FORECAST HAS 15% OR LESS FOR A CHANCE OF SHOWERS OR STORMS
THROUGH MEMORIAL DAY. WE WILL NEED TO MONITOR CLOSELY DAY TO DAY
AND SEE IF WE NEED START INCLUDING A HIGHER CHANCE OF SHOWERS
AND STORMS. IF YOU ARE GETTING A HEAD START ON THE WEEKEND, KEEP
THIS IN MIND AND FIND A WAY TO FOLLOW THE FORECAST TRENDS IN
CASE THINGS DO CHANGE. TRENDS TOWARD THE MIDDLE OF NEXT CONTINUE
TO SHOW AND INCREASING CHANCE OF SHOWERS AND STORMS ALONG WITH
COOLER TEMPERATURES. THE MODELS AND ENSEMBLES ARE STRUGGLING
WITH LOW PRESSURE SETTING UP SHOP OVER THE PACIFIC NORTHWEST OR
SWINGING THAT STORM THROUGH US. THE PROGRESS OF THE LOW WILL
DETERMINE HOW MUCH COOLER IT COULD GET AND HOW LONG ANY CHANCE
OF PRECIPITATION STICKS AROUND. TO GIVE YOU AN IDEA ON THE RANGE
OF TEMPERATURES POSSIBLE, THE OFFICIAL FORECAST HAS HIGHS BY
WEDNESDAY IN THE 60S TO NEAR 70 FOR LOWER ELEVATIONS. THE
WARMEST END OF THE RANGE MAINTAINS HIGHS IN THE 70S AND 80S. THE
COLDEST END OF THE RANGE, WHICH WOULD MORE CLOSELY FOLLOW A
CLOSED SETTLING IN, HAS HIGHS IN THE 40S AND 50S. STAY TUNED.
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
ISSUED AT 1202 PM MDT THU MAY 21 2026
STILL SEEING SOME LINGERING SHOWERS AND A FEW THUNDERSTORMS
ACROSS THE EASTERN HALF OF THE AREA THIS AFTERNOON AS THE REGION
REMAINS ON THE WESTERN EDGE OF AN UPPER TROUGH MOVING THROUGH
WYOMING. KDIJ REMAINS THE MOST LIKELY TERMINAL WITH IMPACTS
FROM TSRA AND MVFR CIGS. KIDA COULD SEE A BRIEF SHOWER UNDER VFR
SKIES WITH MAYBE A BRIEF SHOWER MAKING IT DOWN TO KPIH BUT
CHANCES HERE ARE LOW. KBYI AND KSUN LOOK TO REMAIN DRY. AS THE
TROUGH CONTINUES TO PUSH AWAY, WILL GET SOME BRIEF CLEARING OVER
THE REGION DURING THE LATE EVENING/EARLY OVERNIGHT WITH SOME
SCT/BKN MID/HIGH LEVEL CLOUDS EXPECTED TO RETURN AROUND SUNRISE
TOMORROW. N/NE WINDS 10-15 KTS BECOME MORE LIGHT AND VARIABLE
OVERNIGHT AND INTO THE DAY ON THURSDAY WITH KSUN EXPECTED TO SEE
MORE OF THEIR USUAL DIURNAL CYCLE RETURNING TOMORROW.
FIRE WEATHER
ISSUED AT 1225 AM MDT THU MAY 21 2026
SHOWERS WITH A FEW THUNDERSTORMS WILL PERSIST THROUGH MOST OF
THE DAY, WITH THE BULK OF THE MOISTURE EXPECTED ALONG THE
WYOMING BORDER. THE PORTION OF ZONE 411 IN WESTERN WYOMING WILL
LIKELY SEE THE HIGHEST AMOUNTS OF MOISTURE, 0.20-0.40" WITH
LIGHT SNOW ACCUMULATIONS ON THE HIGHER PEAKS AND RIDGELINES.
THERE HAVE BEEN A FEW THUNDERSTORMS OVERNIGHT, AND WOULD EXPECT
THAT POTENTIAL TO LAST THROUGH THE DAY, WITH AN UPTICK EXPECT
TOWARD SCATTERED COVERAGE POTENTIALLY ACROSS HIGHER TERRAIN FROM
DRIGGS SOUTH THROUGH BEAR LAKE (411 AND 413). GUSTY NORTHERLY
WINDS WILL DEVELOP AS A COLD FRONT SWEEPS SOUTH ACROSS CENTRAL
AND EASTERN IDAHO. HEADING INTO MEMORIAL DAY WEEKEND, TEMPERATURES
RAPIDLY WARM UP TO 10-15 DEGREES ABOVE AVERAGE. THE QUESTION IS
WILL WE REMAIN DRY OR STORM FREE. THERE ARE INDICATIONS THAT
LIMITED MID LEVEL MOISTURE OCCASIONALLY SLIDES ACROSS THE STATE,
WHICH COULD HELP INDUCE AT LEAST SOME VIRGA OR SPRINKLES, OR AN
ISOLATED STORM. RIGHT NOW, THE POTENTIAL FOR THAT IS 15% OR LESS
FOR ANY GIVEN DAY, BUT WE WILL NEED TO MONITOR THIS CLOSELY EACH
DAY TO SEE IF WE NEED TO PUSH THAT POTENTIAL UP A BIT MORE. BY
THE MIDDLE OF NEXT WEEK, ANOTHER ROUND OF SHOWERS AND STORMS
AND COOLER TEMPERATURES ARE EXPECTED.
PIH WATCHES/WARNINGS/ADVISORIES
FROST ADVISORY FROM 3 AM TO 9 AM MDT FRIDAY FOR IDZ052>054.
UPDATE...KEYES
DISCUSSION...KEYES
AVIATION...MCKAUGHAN
FIRE WEATHER...KEYES
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