Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 101649
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 AM PST WED FEB 10 2016

.SYNOPSIS...MOIST SOUTHWEST FLOW ALOFT WILL BRING WET WEATHER TO THE
AREA THROUGH THE WEEKEND. A WEAK FRONT WILL BRING A CHANCE OF RAIN
TODAY AND TONIGHT. RAIN WILL INCREASE AS A WARM FRONT REACHES THE
AREA THURSDAY...FOLLOWED BY A COLD FRONT THURSDAY NIGHT AND FRIDAY.
AN UPPER LEVEL TROUGH WILL PRODUCE SHOWERS FRIDAY NIGHT AND SATURDAY.
ANOTHER FRONT WILL BRING RAIN SUNDAY.

&&

.SHORT TERM...RADAR SHOWS LIGHT RAIN ECHOES OVER THE OLYMPIC
PENINSULA. NUMEROUS SPOTS THERE HAVE RECEIVED A HUNDREDTH OR TWO OF
RAIN. THE FORECAST CONTINUES TO CALL FOR THIS WEAK WEATHER SYSTEM TO
MOVE INLAND TODAY WITHOUT MUCH PUNCH. RAIN WILL BE LIKELY OVER THE
OLYMPIC PENINSULA AND NORTH CASCADES WITH A CHANCE OF RAIN
ELSEWHERE. HIGHS TODAY WILL BE IN THE 50S.

THERE IS A BACK EDGE TO THIS SYSTEM APPARENT ON SATELLITE IMAGERY SO
SOME DRYING IS LIKELY TONIGHT. THE NEXT SYSTEM WILL ARRIVE FROM THE
SOUTHWEST. RECENT MODEL RUNS HAVE SLOWED THIS SYSTEM A BIT...NOW IT
APPEARS MOST OF THE RAIN WILL REACH THE INTERIOR OF WESTERN
WASHINGTON AFTER 00Z FRIDAY. IT WILL RAIN THURSDAY NIGHT...THEN A
COLD FRONT WILL MOVE THROUGH FRIDAY MORNING...GIVING SHOWERS FRIDAY
AFTERNOON. HIGHS WILL REMAIN IN THE MID 50S. BURKE

.LONG TERM...PREVIOUS DISCUSSION...THERE IS GOOD AGREEMENT ON THE
GENERAL PATTERN IN THE EXTENDED MODELS THIS MORNING WITH AN UPPER
LEVEL TROUGH MOVING THROUGH WESTERN WASHINGTON SATURDAY MORNING.
THERE IS A LONG FETCH OF MOISTURE AIMED AT THE PACIFIC NORTHWEST
BEGINNING SATURDAY NIGHT AND CONTINUING THROUGH MONDAY WITH AN UPPER
LEVEL RIDGE BUILDING TO THE SOUTH. THE MODELS HAVE BEEN BOUNCING
AROUND ON JUST HOW STRONG THE RIDGE WILL BE AND IF THE RIDGE WILL BE
STRONG ENOUGH TO PUSH THE MOISTURE NORTH OF WESTERN WASHINGTON. THE
00Z RUNS KEEP THE AREA WET THROUGH SUNDAY THEN TRY TO LIFT THE BAND
NORTH ON MONDAY. CURRENT FORECAST FOLLOWS THIS TREND SO WILL STAY
WIT WITH THE LIKELY POPS SATURDAY NIGHT THROUGH SUNDAY NIGHT AND
CHANCE POPS FOR MONDAY AND TUESDAY IN THE MORNING FORECAST PACKAGE.

&&

.HYDROLOGY...RIVER FLOODING IS UNLIKELY THROUGH SATURDAY. THERE IS
SOME POTENTIAL FOR HEAVY RAIN OVER THE OLYMPICS BEGINNING SATURDAY
NIGHT WHICH COULD CAUSE THE SKOKOMISH RIVER TO FLOOD EARLY NEXT WEEK.

&&

.AVIATION...SW FLOW ALOFT. THE AIR MASS IS STABLE WITH MID AND
HIGH LEVEL MOISTURE THAT WILL GRADUALLY LOWER AND THICKEN AS A WEAK
FRONT MOVES ONSHORE LATE THIS AFTERNOON AND EVENING...AND A WARM
FRONT APPROACHES THE AREA FROM THE SW ON THU.

A WEAK FRONT IS ALONG THE COAST THIS MORNING AND WILL PUSH INLAND
THIS EVENING. RADARS SHOW LIGHT RAIN OVER THE WESTERN OLYMPIC
PENINSULA WITH LIGHT SHOWERS IN THE NORTH INTERIOR. LOW LEVEL
PRESSURE GRADIENTS ARE OFFSHORE...SO PRECIPITATION IN THE INTERIOR
IS VERY LIGHT...FALLING FROM A MID LEVEL CLOUD DECK. MVFR TO LOCAL
IFR CIGS ARE SEEN ALONG THE WASHINGTON COAST. EXPECT CEILINGS TO
GRADUALLY LOWER IN THE INTERIOR THROUGH THIS EVENING...FALLING TO
2000-3000 FT THIS EVENING AS THE FRONT PUSHES INLAND. MAINLY MVFR
CIGS WILL CONTINUE THROUGH TONIGHT. WHILE MID AND HIGH LEVEL
MOISTURE WILL REMAIN ON THU...EXPECT THE LOWER LEVELS TO DRY
SOMEWHAT THU MORNING AS A WARM FRONT WELL TO THE SW APPROACHES THE
AREA AND FORCES LOW LEVEL PRES GRADIENTS TO BECOME MORE
OFFSHORE. ALBRECHT

KSEA...CIGS AROUND 100 WILL GRADUALLY LOWER TO 050 THIS AFTERNOON
AND 025-030 ABOUT 02Z. IMPROVEMENT BACK TO OVC060-080 EXPECTED ABOUT
16Z THU. S WIND 4-8 KT THIS AFTN BECOMING ELY THU MORNING. ALBRECHT

&&

.MARINE...A WEAK FRONT WILL MOVE EAST THROUGH THE COASTAL WATERS
TODAY THEN INLAND THIS EVENING. SMALL CRAFT ADVISORY S TO SE WINDS
ARE EXPECTED OVER THE COASTAL WATERS THROUGH EARLY THIS EVENING.
A FEW HOURS OF SMALL CRAFT ADVISORY SE WINDS CAN ALSO BE EXPECTED IN
ADMIRALTY INLET TODAY AS FLOW ALOFT INTERACTS WITH THE OLYMPICS AND
PRODUCES A MESOSCALE LOW ON THE NE OLYMPIC PENINSULA. WINDS WILL
DIMINISH THIS EVENING BEHIND THE FRONT.

A STRONGER WARM FRONT WILL APPROACH THE WATERS FROM THE SW ON THU.
EXPECT SMALL CRAFT ADVISORY EAST TO SOUTHEAST WINDS TO DEVELOP OVER
THE COASTAL WATERS AND AT THE ENTRANCES TO THE STRAIT ON THU AND
CONTINUE THU NIGHT AS THE WARM FRONT MOVES NE THEN IS FOLLOWED BY A
COLD FRONT THU NIGHT INTO EARLY FRI.

MODERATE ONSHORE FLOW WILL FOLLOW FRI AFTERNOON OR EVENING INTO SAT
MORNING. SMALL CRAFT ADVISORY SOUTH TO SOUTHWEST WINDS CAN BE
EXPECTED IN THE PUGET SOUND AND HOOD CANAL AREA WHILE SMALL CRAFT
ADVISORY WESTERLY FLOW CAN BE EXPECTED OVER THE CENTRAL AND EASTERN
STRAIT OF JUAN DE FUCA.

ANOTHER FRONT WILL AFFECT THE WATERS SAT NIGHT OR SUN. ALBRECHT

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL MIDNIGHT PST TONIGHT 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.

     SMALL CRAFT ADVISORY UNTIL 9 PM PST THIS EVENING FOR ADMIRALTY
     INLET.

&&

$$

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