919
FXUS66 KPDT 250546
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
946 PM PST TUE FEB 24 2026
DISCUSSION
A STATIONARY FRONT DRAPED ACROSS THE PACNW IN COMBINATION WITH
A MOIST SOUTHWEST FLOW ALOFT CONTINUES TO BRING SHOWERY
PRECIPITATION ACROSS THE FORECAST AREA THIS EARLY AFTERNOON.
SATELLITE AND RADAR IMAGERY OVER THE PAST FEW HOURS HAVE SHOWN
AN ATMOSPHERIC RIVER BEGINNING TO SHIFT SOUTHEAST, WITH THE MAIN
BAND OF STEADY PRECIP FOCUSED OVER SOUTHERN PORTIONS OF OREGON.
MEANWHILE, MORE SHOWERY LIGHT PRECIP BANDS ARE DEVELOPING ALONG
PORTIONS OF THE CASCADE CREST, THE LOWER COLUMBIA BASIN AND
ADJACENT VALLEYS/FOOTHILLS, AND THE NORTHERN BLUE MOUNTAINS.
CURRENTLY, ONLY LIGHT SNOW SHOWERS ARE DEVELOPING ALONG THE WA
CASCADE CREST, WHILE LIGHT RAIN AND HIGH MTN PEAK SNOW SHOWERS
ARE DEVELOPING ALONG THE OR CASCADE CREST AND EASTERN MOUNTAINS,
WHERE SNOW LEVELS ARE GENERALLY OVER 6KFT.
TODAY THROUGH WEDNESDAY AFTERNOON: SHOWERY PRECIPITATION WILL
CONTINUE ACROSS THE FORECAST AREA THROUGH WEDNESDAY MORNING,
SHIFTING FROM NORTH TO SOUTH THROUGH THE OVERNIGHT HOURS. THIS
IS DUE TO A MOSTLY OFFSHORE TROUGH CLOSING OFF INTO A LOW, WITH
THE INLAND PORTION (OVER BC), PINCHING OFF INTO A BROAD SHALLOW
TROUGH THAT WILL DROP SOUTHEAST OF THE REGION BY LATE WEDNESDAY
MORNING. WITH THE MAIN AR TO THE SOUTH OF THE FORECAST AREA,
SHOWERS WILL REMAIN LIGHT ACROSS THE LOWER ELEVATIONS, WITH ONLY
A 15-40% CHANCE OF AN ADDITIONAL 0.25 INCHES OF RAIN IN THE
LOWER ELEVATIONS (70-80% CHANCE OF AT LEAST 0.1 INCHES) THIS
AFTERNOON THROUGH EARLY TOMORROW AFTERNOON. AS FOR THE
MOUNTAINS, SNOW LEVELS WILL GRADUALLY DROP TO PASS LEVEL (3 KFT
TO 4 KFT) ACROSS THE OR MOUNTAIN ZONES AS THE SHORTWAVE FORCES A
COOLER AIRMASS INTO THE PACNW TONIGHT. THIS WILL RESULT IN SNOW
AMOUNTS OF 0.5" TO 3 INCHES ACROSS THE PASSES, WA CASCADES, AND
SOUTHERN BLUES, WITH AMOUNTS CLOSER TO 3 TO 5 INCHES IN THE
INTERIOR NORTHERN BLUES, ELKHORN CREST, OR CASCADE CREST, AND
THE EAGLE CAPS (CONFIDENCE 65-85%).
OTHER THAN PRECIP, BREEZY WEST TO SOUTHWEST WINDS (15 TO 25 MPH
WITH GUSTS 25 TO 40 MPH) WILL DEVELOP ACROSS THE FORECAST AREA
AS AN AREA OF SURFACE LOW PRESSURE DEVELOPS OVER THE UPPER
PORTIONS OF THE COLUMBIA BASIN.
DRIER CONDITIONS WILL SETTLE INTO THE REGION BY WEDNESDAY
AFTERNOON AS UPPER LEVEL RIDGING BUILDS ACROSS THE NORTHEAST
PACIFIC, RAISING 500MB HEIGHTS ACROSS THE PACNW.
WEDNESDAY NIGHT THROUGH FRIDAY: THERE IS GOOD AGREEMENT AMONGST
ENSEMBLE AND DETERMINISTIC GUIDANCE THAT THE PACNW WILL BE UNDER
A NORTHWEST FLOW ALOFT AS RIDGING CONTINUES TO BUILD OVER THE
NORTHEAST PACIFIC. THIS WILL RESULT IN MOSTLY DRY CONDITIONS
ACROSS THE FORECAST AREA THROUGH FRIDAY NIGHT. THAT SAID,
UPSLOPE FORCING ALONG THE WA CASCADE CREST WILL BE STRONG ENOUGH
TO WRING OUT ANY LINGERING MOISTURE IN THE FLOW ALOFT AND
PRODUCE LIGHT SNOW FLURRIES, WITH DAILY SNOW AMOUNTS ANYWHERE
FROM A TRACE TO ONE INCH AT SNOQUALMIE AND WHITE PASSES.
AFTERNOON BREEZY WINDS (15 TO 25 MPH WITH GUSTS 25 TO 40 MPH)
WILL CONTINUE TO BE A DAILY OCCURRENCE ACROSS MAINLY THE WA
CASCADE EAST SLOPES/CREST, AND THE COLUMBIA BASIN AND ADJACENT
VALLEYS/FOOTHILLS. THERE IS STRONG AGREEMENT AMONGST ENSEMBLE
AND DETERMINISTIC MODEL GUIDANCE THAT A SURFACE LOW WILL LINGER
ACROSS NORTHERN WA THROUGH FRIDAY, WITH HIGH PRESSURE DEVELOPING
WEST OF THE CASCADES AND OVER THE SAWTOOTH MOUNTAINS IN ID.
SATURDAY THROUGH MONDAY: THROUGH EARLY NEXT WEEK, ENSEMBLE
CLUSTER GUIDANCE INDICATES THAT A CLOSED LOW UNDERCUTTING THE
UPPER RIDGE IN THE NORTHEAST PACIFIC WILL SLOWLY PUSH EAST
TOWARDS NORTHERN CA AND SOUTHERN OR. AS IT APPROACHES, THE
SOUTHERN PORTIONS OF THE FORECAST AREA WILL SEE LIGHT RAIN/SNOW
DEVELOP AS EARLY AS SATURDAY AFTERNOON, WITH LIGHT PRECIP
PERSISTING INTO EARLY NEXT WEEK (CONFIDENCE 50-70%). OTHERWISE,
DRY CONDITIONS WILL PREVAIL ACROSS THE REMAINDER OF THE FORECAST
AREA. LAWHORN/82
AVIATION /06Z TAFS THROUGH 06Z THURSDAY/
RAIN SHOWERS WILL GRADUALLY TAPER OFF FROM NORTHWEST TO
SOUTHEAST OVERNIGHT INTO EARLY WEDNESDAY MORNING. CONFIDENCE IS
VERY HIGH (95 PERCENT) THAT AT LEAST SOME SUB-VFR CONDITIONS --
RANGING FROM VLIFR TO MVFR IN RAIN, LOW STRATUS, AND FG/BR --
WILL PERSIST ACROSS THE REGION OVERNIGHT. WEDNESDAY MORNING,
SKIES ARE EXPECTED TO GRADUALLY BECOME CLEAR OR PARTLY CLOUDY AT
ALL SITES. MEANWHILE, WEST TO SOUTHWEST WINDS WILL RAMP TO
10-15 KTS WITH GUSTS OF 15-25 KTS AT DLS/PDT/ALW/PSC LATER
WEDNESDAY MORNING THROUGH AFTERNOON. 86
PRELIMINARY POINT TEMPS/POPS
PDT 34 47 30 54 / 80 10 0 0
ALW 35 48 33 53 / 80 30 0 0
PSC 33 52 33 55 / 50 0 0 0
YKM 27 49 28 52 / 40 0 0 0
HRI 34 51 30 55 / 60 0 0 0
ELN 26 42 29 46 / 40 10 10 10
RDM 31 46 21 52 / 60 10 0 0
LGD 36 46 25 51 / 90 40 0 0
GCD 37 44 23 49 / 80 40 0 0
DLS 34 48 32 53 / 60 0 0 0
PDT WATCHES/WARNINGS/ADVISORIES
WA...NONE.
OR...NONE.
DISCUSSION...82
AVIATION...86
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page