878
FXUS66 KSEW 172243
AFDSEW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
243 PM PST TUE FEB 17 2026
SYNOPSIS
A BROAD LOW PRESSURE SYSTEM OVER THE NE PACIFIC WILL MOVE
SOUTHEASTWARD THROUGH THURSDAY, KEEPING SCATTERED RAIN AND
OVERNIGHT SNOW SHOWERS IN THE FORECAST THROUGH THEN. COOLER
TEMPERATURES FOLLOW THURSDAY AND FRIDAY WITH FRASER RIVER
OUTFLOW. A WARMER PATTERN RETURNS FRIDAY INTO EARLY NEXT WEEK,
ACCOMPANIED BY A MORE SIGNIFICANT SYSTEM BRINGING GUSTY WINDS,
AS WELL AS ADDITIONAL RAIN AND MOUNTAIN SNOW.
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/
RADAR IMAGERY SHOWS MOSTLY SCATTERED TO ISOLATED SHOWERS ACROSS
WESTERN WASHINGTON, WITH THE HIGHEST CONCENTRATION OF PRECIPITATION
ACROSS THE WESTERN OLYMPIC PENINSULA. THESE SHOWERS ARE BEING
SUPPORTED BY A VERTICALLY-STACKED LOW PRESSURE SYSTEM CURRENTLY
CENTERED OVER THE OFFSHORE WATERS OFF WASHINGTON. THIS LOW/TROUGH
WILL MOVE TO THE SOUTHEAST TONIGHT INTO WEDNESDAY, WHICH WILL ALLOW
FOR AN INCREASE IN SHOWER COVERAGE ONCE AGAIN LATE TONIGHT AND
THROUGH MUCH OF THE DAY WEDNESDAY. TEMPERATURES WILL BE COLD ENOUGH
TO SUPPORT SOME SNOW SHOWERS ACROSS MOST OF THE AREA THROUGH AROUND
9/10 AM WEDNESDAY, IN PARTICULAR ACROSS THE OLYMPIC PENINSULA.
SPECIFIC AMOUNTS AND LOCATIONS ARE DIFFICULT TO DEFINE DUE TO THE
SHOWERY NATURE OF THE PRECIPITATION, BUT MOST ALL LOCATIONS SHOULD
RECEIVE LESS THAN ONE INCH OF ACCUMULATING SNOWFALL BASED ON THE
AMOUNT OF QPF IN THE FORECAST AND THE FACT THAT TEMPERATURES WILL
ALLOW FOR MELTING WEDNESDAY AFTERNOON.
AS THE SYSTEM CONTINUES TO DEPART TO THE SOUTHEAST, PRECIPITATION
WILL BEGIN TO CEASE ACROSS MUCH OF THE AREA BY WEDNESDAY EVENING.
THURSDAY LOOKS TO REMAIN MOSTLY DRY ACROSS THE AREA, WITH BEST
CHANCES FOR CONTINUED LIGHT PRECIPITATION ACROSS THE SOUTH, MAINLY
SOUTH OF OLYMPIA.
LOW TEMPERATURES WEDNESDAY MORNING WILL BE SIMILAR TO TODAY--IN THE
LOW 30S TO UPPER 20S, MAINLY ACROSS THE OLYMPIC PENINSULA AND AWAY
FROM THE SEATTLE METRO. FRASER RIVER OUTFLOW WINDS WILL BEGIN TO
INCREASE TONIGHT, BUT LIMITED TO WESTERN WHATCOM COUNTY, WHERE WIND
CHILLS WILL BEGIN TO DROP TO AROUND 20 DEGREES. HIGH TEMPERATURES
ACROSS THE AREA WILL REMAIN SIMILAR THROUGH WEDNESDAY AND THURSDAY,
IN THE LOW 40S, EXCEPT ACROSS THE NORTHWEST INTERIOR INTO THE STRAIT
OF JUAN DE FUCA WHERE FRASER OUTFLOW WILL HELP KEEP HIGHS DOWN INTO
THE MID TO UPPER 30S. LOW TEMPERATURES WILL BE COOLER AREA-WIDE
THURSDAY MORNING, WITH MOST AREAS IN THE MID TO UPPER 20S. LOWER 20S
ARE POSSIBLE IN WESTERN WHATCOM COUNTY WITH CONTINUED WINDY
CONDITIONS PUSHING WIND CHILLS INTO THE TEENS. FRASER OUTFLOW WINDS
WILL BEGIN TO EASE THURSDAY EVENING.
LONG TERM /FRIDAY THROUGH TUESDAY/
FRIDAY WILL MARK THE START OF A WARMING TREND AS THE COLD TROUGH
GETS PUSHED OUT BY A WEAK UPPER LEVEL RIDGE THAT WILL BEGIN TO BUILD
OVER THE INTERMOUNTAIN WEST OVER THE WEEKEND. ADDITIONALLY, A LARGE
UPPER TROUGH WILL DIG OVER THE NE PACIFIC OUT OF THE GULF OF ALASKA,
WHICH WILL HAVE SEVERAL SHORTWAVES ROTATING THROUGH IT TO THE
NORTHEAST. THIS TROUGH LOOKS TO DEVELOP SEVERAL STRONGER, BUT FAST-
MOVING, LOW PRESSURE SYSTEMS JUST OFFSHORE THIS WEEKEND AND INTO
EARLY NEXT WEEK. THESE SYSTEMS WILL PUSH SNOW LEVELS UP TO AROUND
2000-3000 FT. WHILE QPF AND SNOW AMOUNTS DON'T LOOK TO BE NOTEWORTHY
AT THIS POINT, THESE WILL BE WINDIER SYSTEMS WITH MORE WIDESPREAD
BREEZY TO GUSTY CONDITIONS. A FEW INCHES OF SNOW WILL BE POSSIBLE AT
THE PASSES WILL BE POSSIBLE EACH DAY. TEMPERATURES WILL WARM WITH
HIGHS GOING UP INTO THE MID TO UPPER 40S FRIDAY AND SATURDAY,
REACHING THE LOW 50S SUNDAY AND ONWARD. LOWS RETURN TO THE MID TO
UPPER 30S. IN OTHER WORDS, RIGHT AROUND CLIMATOLOGY FOR THIS TIME OF
YEAR.
62
AVIATION
SOUTHWEST FLOW ALOFT MAINTAINING SCATTERED SHOWERS
THIS AFTERNOON THOUGH COVERAGE IS LIMITED. EXPECT PREDOMINANTLY VFR
CEILINGS THROUGH THE EVENING, THOUGH ANOTHER ROUND OF SHOWERS
OVERNIGHT ROTATES THROUGH THE REGION. THIS WILL SUPPORT ANOTHER
ROUND OF LOWERING CEILINGS AND MIXED MVFR/IFR CONDITIONS IN HEAVIER
SHOWERS. WITH TEMPERATURES COOLING OVERNIGHT, THESE SHOWERS COULD BE
MIXED OR ENTIRELY SNOW. WHILE SNOW ACCUMULATIONS AT THE TERMINALS
REMAIN UNLIKELY, A HEAVY SHOWER COULD BRING A QUICK ACCUMULATION
DOWN TO THE SURFACE. EXPECT MOISTURE TO TAPER AFTER 18Z WEDNESDAY
FOR MOST, AND A RETURN TO PRIMARILY VFR CEILINGS INTO THE BALANCE OF
THE DAY. WINDS REMAIN GENERALLY LIGHT FOR MOST, WITH OFFSHORE WINDS
AT KBLI SOUTHWEST THROUGH KCLM.
KSEA...CEILINGS REMAIN VFR WITH SHOWERS MOSTLY AVOIDING THE TERMINAL
AREA. ADDITIONAL PASSING SHOWERS OVER COULD BRING BRIEF MVFR
CONDITIONS LATE EVENING OR OVERNIGHT. TEMPERATURES COOL DURING THIS
TIME, ALLOWING SOME POTENTIAL FOR SHOWERS TO BECOME SNOW IF THEY GET
HEAVY ENOUGH DURING THIS TIME (GENERALLY 10Z-15Z). WHILE LITTLE TO
NO SNOW ACCUMULATION EXPECTED, IF SHOWERS ARE HEAVY ENOUGH THEY
COULD . WINDS REMAIN GENERALLY LIGHT WESTERLY THIS EVENING, BECOMING
PREDOMINANTLY LIGHT SOUTHERLY OVERNIGHT THROUGH WEDNESDAY.
MARINE
LOW PRESSURE REMAINS OFFSHORE. AS THIS PUSHES INLAND, WINDS WILL
SHIFT DIRECTION BUT SPEEDS REMAIN WELL BELOW ADVISORY THRESHOLDS.
HOWEVER, SEAS REMAIN 10-12 FT OVER THE COASTAL WATERS AND WESTERN
ENTRANCE OF THE STRAIT. WITH FRASER OUTFLOW INCREASING, SOME
OCCASIONAL GUSTS TO 20-25 KT ARE POSSIBLE THURSDAY MORNING ACROSS
THE NORTHERN INLAND WATERS. OTHERWISE, ATTENTION TURNS TO THE NEXT
FRONTAL SYSTEM LATE IN THE WEEK WITH INCREASING WINDS OVER THE
WATER AND THE RETURN OF SEAS INTO THE 15-17 FT RANGE BY LATE IN
THE WEEKEND.
HYDROLOGY
NO RIVER FLOODING IS EXPECTED IN THE NEXT SEVEN DAYS.
SEW WATCHES/WARNINGS/ADVISORIES
WA...COLD WEATHER ADVISORY FROM 1 AM TO 10 AM PST WEDNESDAY FOR
LOWLANDS OF WESTERN WHATCOM COUNTY.
PZ...SMALL CRAFT ADVISORY UNTIL 4 AM PST WEDNESDAY FOR GRAYS HARBOR
BAR.
SMALL CRAFT ADVISORY UNTIL 8 AM PST WEDNESDAY FOR COASTAL
WATERS FROM CAPE FLATTERY TO JAMES ISLAND 10 TO 60 NM-
COASTAL WATERS FROM CAPE FLATTERY TO JAMES ISLAND OUT 10
NM-COASTAL WATERS FROM JAMES ISLAND TO POINT GRENVILLE 10
TO 60 NM-COASTAL WATERS FROM JAMES ISLAND TO POINT
GRENVILLE OUT 10 NM-COASTAL WATERS FROM POINT GRENVILLE
TO CAPE SHOALWATER 10 TO 60 NM-COASTAL WATERS FROM POINT
GRENVILLE TO CAPE SHOALWATER OUT 10 NM-WEST ENTRANCE U.S.
WATERS STRAIT OF JUAN DE FUCA.
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