379
FXUS66 KSEW 121008
AFDSEW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
208 AM PST WED NOV 12 2025
SYNOPSIS
A FRONTAL SYSTEM WILL CONTINUE MOVING THROUGH THE REGION TODAY
FOR RAIN AND SOME MOUNTAIN SNOW THROUGH THURSDAY. THE BACK HALF
OF THE WEEK LOOKS TO REMAIN ACTIVE, THOUGH NO SIGNIFICANT
IMPACTS ARE FORECAST. ADDITIONAL WEATHER SYSTEMS ARE LIKELY INTO
THIS WEEKEND.
SHORT TERM /TODAY THROUGH FRIDAY/
SOME PRE-FRONTAL SHOWERS HAVE DEVELOPED ACROSS PORTIONS OF
THURSTON, LEWIS AND PIERCE COUNTIES, AND ARE GENERALLY MOVING TO
THE NORTHEAST INTO THE CASCADES. ADDITIONAL RAINFALL WILL ARRIVE
LATER THIS MORNING AND FAVOR THE NORTH CASCADES, AND AREAS
GENERALLY FROM SEATTLE SOUTH. MORE WIDESPREAD PRECIPITATION WILL
ARRIVE LATE THIS AFTERNOON INTO THURSDAY AS THE LOW APPROACHES
THE AREA. THE GENERAL INDICATION AT THIS POINT IS FOR THE LOW TO
REACH THE OREGON/CALIFORNIA COAST. STORM TOTAL QPF AMOUNTS
THROUGH FRIDAY AFTERNOON SHOW ABOUT THREE QUARTERS OF AN INCH OF
RAIN THROUGHOUT PUGET SOUND, AND 1 TO 2 INCHES IN THE CASCADES
AND ADJACENT FOOTHILLS. ISOLATED AMOUNTS OF UP TO 4 INCHES COULD
FALL IN THE NORTH CASCADES, BUT SOME OF THAT IS EXPECTED TO FALL
AS SNOW AS THE SNOW LEVELS COME DOWN EARLY FRIDAY MORNING TO
AROUND 3400 FEET. WHILE THE CHANCES OF ACCUMULATING SNOW FAVOR
THE NORTH CASCADES, LIGHT AMOUNTS CANNOT BE FULLY RULED OUT AT
STEVENS PASS. THE POTENTIAL FOR MIXED PRECIPITATION IS STILL IN
PLAY FOR SNOQUALMIE PASS, BUT CONFIDENCE IS LESS ON SNOW AMOUNTS
IN THAT REGION.
TEMPERATURES WILL BE IN THE UPPER 50S TO LOW 60S TODAY AND
THURSDAY, DROPPING BACK INTO THE LOW 50S ON FRIDAY.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/
AS THE LOW DROPS DOWN TO THE SOUTH AND CLOSES OFF ON FRIDAY, THE
PACNW WILL GENERALLY BE LEFT WITH UPPER LEVEL ZONAL FLOW,
ALLOWING FOR ADDITIONAL SYSTEMS TO ARRIVE INTO THE WEEKEND.
ADDITIONAL BUT SHORT LIVED SYSTEMS WILL ARRIVE THROUGH THE
WEEKEND FOR ADDITIONAL RAIN CHANCES WITH MORE MOUNTAIN SNOW
POTENTIAL. SNOW LEVELS SEEM LIKELY TO RISE AGAIN ON SATURDAY AND
SUNDAY, BUT COME DOWN AGAIN FOR A LIGHT ACCUMULATION AGAIN
FAVORING THE NORTH CASCADES. WEEKEND THROUGH MONDAY MORNING
RAINFALL AMOUNTS INDICATE ANOTHER 1-3 INCHES IN THE OLYMPICS
AND CASCADES, AND ANOTHER HALF TO THREE QUARTERS OF AN INCH IN
THE LOWLANDS.
THE CPC PROBABILISTIC HAZARDS SHOW A SLIGHT RISK FOR HEAVY
PRECIPITATION VALID THE 19TH THROUGH THE 25TH OF THIS MONTH, AS
WELL AS A SLIGHT RISK FOR MOUNTAIN SNOW IN THE SAME TIME FRAME.
THE EXTENDED FORECAST MAY INDICATE MORE ACTIVE WEATHER ON THE
WAY, BUT THERE'S QUITE A WAY TO GO FOR ANY SOLID CONSENSUS TO
EMERGE YET.
21
AVIATION
A WEAK WARM FRONT WILL LIFT NORTH THROUGH WESTERN WA
TODAY FOR LIGHT RAIN. THE FLOW ALOFT IS WEST TO SOUTHWEST. THERE
ARE POCKETS OF LOW CLOUDS AND FOG AROUND THE SOUTH SOUND,
OTHERWISE CONDITIONS ARE MOSTLY VFR. RAIN INCREASES IN COVERAGE
TONIGHT AS A WEAK SURFACE FRONT SHIFT INLAND, WITH MVFR
CONDITIONS EXPECTED. 33
KSEA...VFR TODAY WITH LIGHT RAIN IN THE VICINITY. EASTERLY WINDS
5 KT OR LESS. LOWER CLOUDS, MVFR CONDITIONS, AND RAIN EARLY
THURSDAY MORNING. 33
MARINE
EXPECT INCREASING S/SE WINDS OVER THE COASTAL WATERS TODAY AND
THURSDAY DUE TO APPROACHING LOW PRESSURE OVER THE OFFSHORE
WATERS. SEAS WILL ALSO BUILD TO 10 TO 13 FEET. STRONG ONSHORE
FLOW WILL FOLLOW THURSDAY NIGHT AS LOW PRESSURE SHIFTS INLAND.
HIGHEST WIND/WAVES WILL BE FOUND THE STRAIT OF JUAN DE FUCA.
ADDITIONAL FRONTS WILL REACH THE AREA FRIDAY AND OVER THE
WEEKEND, KEEPING THE PATTERN ACTIVE. 33
HYDROLOGY
DRY CONDITIONS WILL CONTINUE TODAY, BEFORE A SERIES OF SYSTEMS
MOVES ACROSS THE REGION MID TO LATE WEEK. WHILE THE SECOND HALF
OF THE WEEK WILL BE WETTER, THE SYSTEMS LOOK TO REMAIN RATHER
PROGRESSIVE AT THIS TIME. RISES WILL BE POSSIBLE ON AREA RIVERS
OVER THE WEEKEND, MOST NOTABLY ON THE SKOKOMISH RIVER IN MASON
COUNTY. HOWEVER, AT THIS TIME, NO RIVER FLOODING IS EXPECTED.
14
SEW WATCHES/WARNINGS/ADVISORIES
WA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM PST
FRIDAY 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.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page