Small Craft Advisory for Winds 5, NWS Seattle, WA

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SEATTLE WA
952 PM PST SUN JAN 22 2012

UPDATED THE SHORT TERM...AVIATION...MARINE SEGMENTS...AND MARINE
HAZARDS.

.SYNOPSIS...A STRONG FRONT ASSOCIATED WITH A DEEP LOW MOVING ONTO
NORTHERN VANCOUVER ISLAND WILL PUSH EAST OF THE AREA THIS EVENING.
ONSHORE FLOW AND SHOWERS WILL GRADUALLY DIMINISH OVERNIGHT. MONDAY
WILL SEE A BREAK IN THE ACTIVE WEATHER IN BETWEEN SYSTEMS. WET
WEATHER WILL RETURN TUESDAY THROUGH THURSDAY. HIGH PRESSURE WILL
GIVE DRIER WEATHER FRIDAY. A COLD FRONT WILL ARRIVE SATURDAY.

&&

.SHORT TERM...THE DEEP LOW THAT MOVED NORTH THROUGH THE OFFSHORE
WATERS THIS AFTERNOON IS NOW DECAYING AS IT MOVES ONSHORE EAST OF
NORTHERN VANCOUVER ISLAND. THE LEFT OVER BENT BACK OCCLUSION
WRAPPING AROUND THE SOUTH SIDE OF THIS LOW CONTINUES TO PRODUCE
STORM FORCE WINDS ALONG THE WEST COAST OF VANCOUVER ISLAND. THESE
WINDS BRUSHED CAPE FLATTERY EARLIER THIS EVENING WITH OVER 60 MPH
WINDS. THE BENT BACK OCCLUSION WILL CONTINUE TO WEAKEN AS IT LIFTS
NORTH OF THE AREA THIS EVENING. HIGH WINDS WERE REPORTED ALONG THE
NORTH COAST OF WESTERN WASHINGTON...BUT IT APPEARS THAT THE WIND
SPEEDS OVER THE NORTH INTERIOR AND ALONG THE CENTRAL WASHINGTON
COAST FELL JUST SHORT OF HIGH WIND CRITERIA. IN ANY CASE...EXPECT
WINDS TO DIMINISH OVERNIGHT FROM SOUTH TO NORTH AS THE LOW AND ITS
ASSOCIATED OCCLUSION FEATURE LIFTS NORTH AND WEAKENS. HIGH WIND
WARNINGS AND ADVISORIES WERE CANCELLED AROUND 830 PM.

SHOWERS ALONG THE COAST AND IN THE INTERIOR WILL GRADUALLY BECOME
SCATTERED OVERNIGHT. CONVERGENCE ENHANCING SHOWERS FROM THE
NORTHEASTERN OLYMPICS INTO WESTERN SKAGIT AND WESTERN WHATCOM
COUNTIES WILL GRADUALLY DIMINISH. SHOWERS MOVING INTO THE MOUNTAINS
IN STRONG POST FRONTAL ONSHORE FLOW WILL CONTINUE TO PRODUCE
OCCASIONALLY HEAVY SNOW IN THE MOUNTAINS. WILL ALLOW THE WINTER
WEATHER ADVISORIES FOR THE CASCADES AND OLYMPICS TO CONTINUE THROUGH
4 AM AS SCHEDULED.

SEAS OF 18 TO 22 FEET...WITH WEST SWELLS...WILL CONTINUE TO BATTER
THE COAST THROUGH MONDAY MORNING FOR HIGH SURF CONDITIONS. EXPECT
THE SEAS TO SUBSIDE MONDAY AFTERNOON. TIDES WERE RUNNING 1 TO 2 FEET
HIGHER THAN PREDICTED THIS EVENING...HOWEVER PRESSURES WERE RISING
RAPIDLY IN THE WAKE OF THE FRONT THAT MOVED THROUGH EARLIER. THUS
THE HIGH TIDE MON MORNING SHOULD BE CLOSE TO THE PREDICTION. THE
PREDICTED HIGH TIDE AT LA PUSH IS 9.41 FEET ABOUT NOON MON. SEAS
WILL BE COMING DOWN BY THAT TIME AND SHOULD BE CLOSE TO 15 FEET.

THESE CONDITIONS WILL MAINTAIN A RISK OF SEVERE EROSION OF THE JETTY
PROTECTING THE TOWN OF LA PUSH AND THE LOWER QUILEUTE TRIBAL VILLAGE
THROUGH MONDAY...THUS THE COASTAL FLOOD WATCH WILL REMAIN IN EFFECT.

WEAK HIGH PRESSURE WILL MOVE ACROSS THE AREA MONDAY MORNING THEN
SHIFT EAST OF THE CASCADES MONDAY AFTERNOON AND EVENING. LOW LEVEL
FLOW WILL GRADUALLY BECOME LIGHT OFFSHORE DURING THE AFTERNOON AND
EVENING HOURS. THE RIDGE ALOFT IS RATHER WEAK AND DIRTY...SO WILL
KEEP ISOLATED SHOWERS AND AT LEAST PARTLY CLOUDY SKIES IN THE
FORECAST MONDAY INTO MONDAY EVENING.

A FRONTAL SYSTEM CARRYING SOME TROPICAL MOISTURE FROM THE CENTRAL
PACIFIC WILL MOVE ACROSS THE AREA TUESDAY AND TUESDAY NIGHT THEN
WILL LIKELY DROP SOUTH OF THE AREA INTO FAR SOUTHWEST WASHINGTON OR
OREGON ON WEDNESDAY.

SHORT TERM FORECASTS FOR DIMINISHING WINDS TONIGHT AND LESS
CLOUDINESS AND SHOWER ACTIVITY ON MONDAY HAVE BEEN UPDATED. ALBRECHT

.LONG TERM...PREVIOUS LONG TERM DISCUSSION FOLLOWS...A COLD FRONT
WILL SAG THROUGH THE AREA THURSDAY WITH RAIN DECREASING AND LOWERING
SNOW LEVELS. HIGH PRESSURE WILL BUILD OVER THE AREA FRIDAY FOR
MAINLY DRY WEATHER. LONG RANGE MODELS START TO DIVERGE SIGNIFICANTLY
BEGINNING SATURDAY. THE ECMWF SHOWS A WET FRONTAL SYSTEM MOVING
THROUGH SATURDAY. 19

&&

.HYDROLOGY...AFTER A LULL IN PRECIPITATION LATER TONIGHT THROUGH
MONDAY NIGHT...ANOTHER WET PERIOD IS EXPECTED OVER PORTIONS OF THE
AREA TUESDAY THROUGH THURSDAY. MOISTURE ORIGINATING FROM THE
TROPICAL CENTRAL PACIFIC WITH PRECIPITABLE WATER VALUES ON THE ORDER
OF 1.3 TO 1.7 INCHES IS EXPECTED TO MOVE INTO THE PACIFIC
NORTHWEST...MAINLY INTO SOUTHWEST WASHINGTON AND OREGON.

MODERATE TO HEAVY RAIN IS EXPECTED OVER MAINLY THE SOUTHERN HALF OF
WESTERN WASHINGTON TUESDAY MORNING THROUGH EARLY WEDNESDAY.
WIDESPREAD 24 HOUR RAINFALL AMOUNTS ENDING EARLY WEDNESDAY MORNING
OF 1 TO 2.5 INCHES OF CAN BE EXPECTED OVER THE LOWLANDS FROM MASON
AND GRAYS HARBOR COUNTY SOUTHWARD INTO LEWIS COUNTY. THE OLYMPICS
AND CENTRAL CASCADES WILL LIKELY SEE 24 HOUR PRECIPITATION AMOUNTS
1.5 TO 3.5 INCHES BY EARLY WEDNESDAY.  SNOW LEVELS OF 2500 FEET
TUESDAY WILL RISE TO 5000 FEET TUESDAY NIGHT AND WEDNESDAY.

THE HEAVIEST RAIN WILL LIKELY SHIFT SOUTH INTO NORTHERN OREGON
AND FAR SOUTHWEST WASHINGTON LATER WEDNESDAY INTO WEDNESDAY
NIGHT...THEN DROP INTO CENTRAL AND SOUTHERN OREGON ON THURSDAY. BY
EARLY THURSDAY MORNING...ADDITIONAL 24 HOUR RAINFALL AMOUNTS OF 0.75
TO 1.5 INCHES CAN BE EXPECTED IN THE LOWLANDS OF SOUTHWEST
WASHINGTON WITH 1 TO 3 INCHES IN THE CASCADES. SNOW LEVELS WILL BE
AROUND 4000 FEET.

ANOTHER RELATIVELY DRY PERIOD IS EXPECTED ACROSS THE AREA LATER
THURSDAY OR THURSDAY NIGHT INTO EARLY SATURDAY FOLLOWED BY A
PROGRESSIVE FRONTAL SYSTEM LATER NEXT WEEKEND.

AT THIS TIME IT APPEARS THAT THE GREATEST THREAT OF FLOODING
WEDNESDAY OR THURSDAY WOULD BE ALONG PORTIONS OF THE CHEHALIS RIVER
AND THE SKOKOMISH RIVER. OTHER RIVERS IN SOUTHWEST WASHINGTON COULD
SEE FLOODING IF THE FRONTAL BAND LINGERS A LITTLE FARTHER NORTH THAN
CURRENTLY FORECAST. THE FLOOD THREAT IS EXPECTED TO DIMINISH LATER
THURSDAY INTO SATURDAY.  ALBRECHT

&&

.AVIATION...WLY FLOW ALOFT AND LOW LEVEL ONSHORE FLOW WILL PREVAIL
ACROSS THE AREA OVERNIGHT IN THE WAKE OF THE SYSTEM THAT MOVED
THROUGH EARLIER. ANTICIPATE GENERALLY VFR CONDITIONS THE REST OF
TONIGHT BUT THERE WILL BE AREAS OF CIGS MAINLY IN THE 2-3K FT RANGE.

KSEA...ANTICIPATE VFR CONDITIONS TIL ABOUT 0900 UTC...THEN EXPECT A
BROKEN LAYER NEAR 3K FT TO DEVELOP OVER THE TERMINAL AND PERSIST
THROUGH 1800 UTC. WINDS WILL CONTINUE TO DIMINISH OVERNIGHT.

&&

.MARINE...
ONSHORE FLOW WILL PREVAIL ACROSS THE AREA IN THE WAKE OF THE
OCCLUDED FRONT THAT MOVED THROUGH EARLIER. MEANWHILE...HAZARDOUS
SEAS WILL CONTINUE ON THE COASTAL WATERS AND WEST ENTRANCE TO THE
STRAIT OF JUAN DE FUCA THROUGH MON MORNING. EXPECT ANOTHER STRONG
FRONTAL SYSTEM TO IMPACT THE REGION ON TUE.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WINTER WEATHER ADVISORY FOR THE CASCADES AND OLYMPICS TONIGHT.

     HIGH SURF ADVISORY FOR THE COAST THROUGH MONDAY.

     COASTAL FLOOD WATCH FOR LA PUSH AND THE QUILEUTE LOWER
       VILLAGE THROUGH MONDAY MORNING.

PZ...GALE WARNINGS REMAIN IN EFFECT FOR THE COASTAL WATERS FROM
     CAPE FLATTERY TO JAMES ISLAND OUT TO 60 NM...THE CENTRAL/
     EASTERN STRAIT OF JUAN DE FUCA...NORTHERN INLAND WATERS...
     AND PUGET SOUND/HOOD CANAL.

     SMALL CRAFT ADVISORIES REMAIN IN EFFECT FOR THE REMAINING
     WATERS EXCEPT THE ADMIRALTY INLET.

     SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 6 PM PST MONDAY
     FOR THE GRAYS HARBOR BAR.

&&

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