Small Craft Advisory 51, NWS Seattle, WA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
907 PM PST TUE MAR 1 2016

.SYNOPSIS...SHOWERS WILL CONTINUE TONIGHT AND WINDS WILL EASE. THERE
WILL BE A BREAK BETWEEN WEATHER SYSTEMS DURING THE DAY ON WEDNESDAY
AND THEN ANOTHER FRONT WILL REACH THE AREA WEDNESDAY EVENING. AN
ACTIVE WEATHER PATTERN WILL PERSIST THROUGH THE WEEKEND.

&&

.SHORT TERM...THE WEATHER IS STARTING TO CALM DOWN TONIGHT...AFTER A
ROUND OF HIGH WIND...HEAVY RAIN AND MOUNTAIN SNOW...AND
THUNDERSTORMS TOO. WINDS ARE EASING AND THE WIND ADVISORIES WILL
EXPIRED AT 900 PM AS PLANNED. THE UPPER TROUGH HAS PUSHED EAST OF
THE CREST AND THUNDERSTORM ACTIVITY ACROSS WESTERN WA IS OVER. THE
ONLY ADJUSTMENT IS TO ADD A WINTER WEATHER ADVISORY FOR THE CASCADES
TONIGHT. SNOW LEVELS WILL DROP TO AROUND 3000 FT WITH SNOW
ACCUMULATIONS OF 3-8 INCHES POSSIBLE.

THERE WILL BE A BREAK IN THE WEATHER ON WEDNESDAY AS A WEAK RIDGE
MOVES OVERHEAD AND THE SURFACE FLOW FLIPS TO OFFSHORE. THE NEXT
FRONTAL SYSTEM WILL ARRIVE WEDNESDAY NIGHT ALTHOUGH THIS SYSTEM
LOOKS WEAKER COMPARED TO THE ONE TODAY. A WEAK UPPER LEVEL
DISTURBANCE WILL KEEP SHOWERS IN THE FORECAST ON THURSDAY. TEMPS
WILL BE CLOSE TO NORMAL THROUGH THE PERIOD. 33

.LONG TERM...PREVIOUS DISCUSSION...THERE WILL CONTINUE TO BE PERIODS
OF RAIN OR SHOWERS WITH BREAKS BETWEEN SYSTEMS. THE 12Z GFS SHOWED A
RUN OF THE MILL FRONT ARRIVING FRIDAY MORNING...A STRONGER SYSTEM
FRIDAY NIGHT INTO SATURDAY MORNING...AND YET ANOTHER WEATHER SYSTEM
ON SUNDAY. THE SYSTEM ON SUNDAY HAS A 974MB LOW CENTER THAT MOVES
NORTH THROUGH THE COASTAL OR NEAR OFFSHORE WATERS SUNDAY NIGHT.

&&

.HYDROLOGY...HEAVY RAIN IN THE OLYMPICS FORCED THE SKOKOMISH RIVER
INTO FLOOD STAGE. THE RIVER WILL CREST AND RECEDE WEDNESDAY MORNING.
THE EXISTING FLOOD STAGE OF 16.5 FEET WILL OFFICIALLY BE RAISED TO
17.0 FEET ON MARCH 6TH.

ELSEWHERE...RIVER FLOODING IS NOT EXPECTED FOR THE NEXT 7 DAYS.

&&

.AVIATION...A VIGOROUS FRONTAL SYSTEM IS MOVING THROUGH THE FORECAST
AREA THIS EVENING...AND WILL EXIT THE AREA TO THE EAST WITHIN THE
NEXT FEW HOURS. HIGH PRESSURE ALOFT WILL MOVE OVER THE AREA LATER
TONIGHT AND WEDNESDAY MORNING WITH EASING SOUTHERLY FLOW AT THE
SURFACE. ANOTHER FRONT WILL REACH THE AREA LATE IN THE DAY
WEDNESDAY. THE AIR MASS IS MOIST AND SLIGHTLY UNSTABLE THIS
EVENING...THEN BECOME STABLE WEDNESDAY MORNING.

KSEA...CEILING GENERALLY 3000-5000 FEET. LOW CLOUDS WILL LIKELY
SCATTER AROUND MIDDAY WEDNESDAY WITH MID AND HIGH CLOUDS REMAINING.
THE THREAT OF THUNDERSTORMS APPEARS TO BE OVER FOR THE EVENING.
SOUTH WIND 15 TO 25 KNOTS WITH GUSTS TO 35 KNOTS...EASING LATE
TONIGHT. MCDONNAL

&&

.MARINE...A VIGOROUS FRONT IS MOVING THROUGH THE AREA THIS EVENING.
GALES HAVE ENDED THOUGH FOR THE NORTHERN COASTAL WATERS...WEST
ENTRANCE STRAIT...CENTRAL STRAIT...AND ADMIRALTY INLET. ANOTHER
STRONG FRONT WILL MOVE THROUGH THE WATERS LATE WEDNESDAY AND
WEDNESDAY NIGHT...AND GALE WATCHES HAVE BEEN ISSUED FOR MANY OF THE
MARINE ZONES. THIS WILL FOLLOWED BY ADDITIONAL STRONG WEATHER
SYSTEMS ROUGHLY FRIDAY MORNING AND SATURDAY MORNING. MCDONNAL

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WINTER WEATHER ADVISORY UNTIL 9 AM PST WEDNESDAY FOR CASCADES OF
     PIERCE AND LEWIS COUNTIES-CASCADES OF SNOHOMISH AND KING
     COUNTIES-CASCADES OF WHATCOM AND SKAGIT COUNTIES.

PZ...GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY EVENING
     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.

     GALE WARNING UNTIL 4 AM PST WEDNESDAY FOR 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.

     SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 3 AM PST THURSDAY FOR
     GRAYS HARBOR BAR.

     SMALL CRAFT ADVISORY UNTIL 3 PM 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-WEST
     ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA.

     GALE WATCH FROM WEDNESDAY EVENING THROUGH LATE WEDNESDAY NIGHT
     FOR CENTRAL U.S. WATERS STRAIT OF JUAN DE FUCA-EAST
     ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA-NORTHERN INLAND
     WATERS INCLUDING THE SAN JUAN ISLANDS.

     SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM PST WEDNESDAY
     FOR EAST ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA-
     NORTHERN INLAND WATERS INCLUDING THE SAN JUAN ISLANDS.

     GALE WARNING UNTIL MIDNIGHT PST TONIGHT FOR EAST ENTRANCE U.S.
     WATERS STRAIT OF JUAN DE FUCA-NORTHERN INLAND WATERS
     INCLUDING THE SAN JUAN ISLANDS.

     SMALL CRAFT ADVISORY UNTIL NOON PST WEDNESDAY FOR CENTRAL U.S.
     WATERS STRAIT OF JUAN DE FUCA-PUGET SOUND AND HOOD CANAL.

     SMALL CRAFT ADVISORY UNTIL 6 AM PST THURSDAY FOR ADMIRALTY INLET.

&&

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