Small Craft Advisory 68, NWS Seattle, WA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
301 PM PDT WED MAR 23 2016

.SYNOPSIS...RAIN WILL CHANGE TO SHOWERS TONIGHT AS A FRONT MOVES
THROUGH. THURSDAY WILL BE COOL AND SHOWERY WITH STRONG ONSHORE
FLOW. SNOW WILL FALL IN THE MOUNTAINS...ESPECIALLY ABOVE 3000
FEET. SHOWERS WILL DECREASE FRIDAY. A WEAK FRONTAL SYSTEM WILL
MOVE THROUGH SATURDAY OR SATURDAY NIGHT...WITH RAIN TURNING TO
SHOWERS SUNDAY. DRY WEATHER IS LIKELY NEXT WEEK.

&&

.SHORT TERM...A FRONT WILL BRING RAIN AT TIMES THIS EVENING. RAIN
WILL CHANGE TO SHOWERS LATER TONIGHT. SHOWERS WILL CONTINUE
THURSDAY AND THURSDAY NIGHT IN MOIST SLIGHTLY UNSTABLE ONSHORE
FLOW. DRIER NORTHERLY FLOW WILL DEVELOP FRIDAY WITH SHOWERS
TAPERING AND ENDING BY EVENING. A WEAKER FRONT WILL REACH THE AREA
SATURDAY. LATEST MODELS SHOW THE FRONT FIZZLING OFFSHORE AND IT
MIGHT NOT AMOUNT TO ANYTHING FOR THE INTERIOR

IT WILL BE BREEZY TO WINDY TONIGHT WITH THE FRONT. WINDS ARE
EXPECTED TO STAY BELOW ADVISORY LEVELS BUT THE COAST AND PARTS OF
THE NORTH INTERIOR COULD GET CLOSE. BREEZY CONDITIONS WILL PERSIST
THURSDAY AND THURSDAY NIGHT IN STRONG LOW LEVEL ONSHORE FLOW.

THERE WILL ALSO BE A GOOD AMOUNT OF SNOW IN THE MOUNTAINS OVER THE
NEXT 36 HOURS OR SO. SNOW LEVELS WILL BE 4000-4500 FEET
TONIGHT...THEN LOWER TO 2500 TO 3000 FEET THURSDAY AS AN UPPER
TROUGH MOVES OVER THE AREA. HEAVY SNOW DOES NOT LOOK LIKELY BUT
ADVISORY AMOUNTS SEEM PROBABLE. A PUGET SOUND CONVERGENCE ZONE
COULD LOCALLY ENHANCE AMOUNTS IN THE CENTRAL CASCADES THURSDAY AND
THURSDAY NIGHT. SCHNEIDER

.LONG TERM...SUNDAY WILL BE SHOWERY WITH AN UPPER TROUGH OVER THE
AREA. DRIER NORTHERLY FLOW ALOFT WILL DEVELOP MONDAY AS AN UPPER
RIDGE AMPLIFIES OFFSHORE. SHOWERS SHOULD TAPER AND BE MOSTLY
CONFINED TO THE MOUNTAINS. THE UPPER RIDGE WILL BUILD FURTHER AND
LOW LEVEL FLOW WILL TURN OFFSHORE TUESDAY AND WEDNESDAY. MOSTLY
SUNNY WEATHER WITH HIGHS WARMING TO NEAR 60 ARE EXPECTED.
SCHNEIDER

&&

.AVIATION...ONSHORE FLOW WILL INCREASE BEHIND A COLD FRONT TONIGHT.
THE FLOW ALOFT IS WESTERLY. THE AIR MASS IS MOIST...BECOMING
UNSTABLE TONIGHT WITH SHOWERS ACROSS THE REGION. MVFR CIGS ARE
LIKELY. WINDS BECOMING W/SW BEHIND THE COLD FRONT WITH GUSTS TO 20-
30 KT POSSIBLE.

KSEA...SHOWERS TONIGHT AS A COLD FRONT MOVES INLAND. SW WINDS 10-
15KT WITH GUSTS TO 25 KT BY 06Z. MVFR CIGS LIKELY TONIGHT. 33

&&

.MARINE...ONSHORE FLOW WILL INCREASE BEHIND A COLD FRONT TONIGHT.
SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL WATERS. MODERATE TO
STRONG ONSHORE FLOW WILL CONTINUE ON THURSDAY...THEN GRADUALLY EASE
ON FRIDAY. MEANWHILE...WEST SWELLS WILL BUILD TO 15 TO 18 FEET. THE
FLOW WILL BRIEFLY TURN OFFSHORE AHEAD OF THE NEXT WEAK SYSTEM ON
SATURDAY. ANOTHER WEAK SYSTEM WILL PUSH INLAND ON SUNDAY. 33

&&

.HYDROLOGY...RIVER FLOODING IS UNLIKELY FOR THE NEXT 7 DAYS.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WINTER WEATHER ADVISORY UNTIL 5 AM PDT FRIDAY FOR CASCADES OF
     PIERCE AND LEWIS COUNTIES-CASCADES OF SNOHOMISH AND KING
     COUNTIES-CASCADES OF WHATCOM AND SKAGIT COUNTIES.

PZ...SMALL CRAFT ADVISORY UNTIL 6 PM PDT THURSDAY 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-NORTHERN INLAND WATERS INCLUDING THE
     SAN JUAN ISLANDS-PUGET SOUND AND HOOD CANAL-WEST ENTRANCE
     U.S. WATERS STRAIT OF JUAN DE FUCA.

     SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 5 AM PDT FRIDAY FOR
     GRAYS HARBOR BAR.

     SMALL CRAFT ADVISORY UNTIL 11 PM PDT THURSDAY FOR CENTRAL U.S.
     WATERS STRAIT OF JUAN DE FUCA-EAST ENTRANCE U.S. WATERS
     STRAIT OF JUAN DE FUCA.

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

&&

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