Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 191618
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 AM PDT SUN OCT 19 2014

.SYNOPSIS...AN UPPER RIDGE WILL GIVE DRY AND WARMER WEATHER TODAY
OVER THE INTERIOR WHILE THE NEXT FRONT APPROACHES THE COAST. THE
FRONT WILL BRING RAIN TO THE COAST THIS AFTERNOON...AND TO THE
INTERIOR TONIGHT AND MONDAY. THE ASSOCIATED UPPER LEVEL TROUGH WILL
FOLLOW MONDAY NIGHT. ANOTHER FRONT WILL REACH THE AREA TUESDAY.
MOIST SOUTHWEST FLOW ALOFT WILL CONTINUE THE REST OF NEXT WEEK.

&&

.SHORT TERM...PARTLY SUNNY SKIES ARE IN STORE FOR WESTERN WASHINGTON
TODAY EXCEPT FOR THE COAST AND OLYMPICS WHERE CLOUDS FROM AN
APPROACHING SYSTEM ARE ALREADY MOVING IN. HIGHS OVER THE INTERIOR
WILL BE 65-70 AFTER OVERNIGHT LOWS 55-60. RAIN WILL DEVELOP IN THE
AFTERNOON ON THE COAST AND HIGHS THERE WILL BE IN THE LOW 60S.

RAIN WILL SPREAD INLAND TONIGHT...THEN TURN TO SHOWERS MONDAY. THE
NEXT SYSTEM WILL ARRIVE TUESDAY NIGHT. HIGHS WILL BE AROUND 60 WITH
LOWS AROUND 50 BOTH MONDAY AND TUESDAY. BURKE

.LONG TERM...PREVIOUS DISCUSSION...CONFIDENCE IN THE LONG TERM
FORECAST REMAINS LOW AT THIS POINT. BOTH THE GFS AND EURO DISAGREE
ON THE STRENGTH OF A RIDGE OVER THE WESTERN CONUS ON FRI. THE EURO
MAINTAINS DRY WEATHER WITH THE RIDGE...WHILE THE GFS BRINGS AN UPPER
LOW INLAND FOR MORE RAIN. AN UPPER LEVEL TROUGH MAY CROSS THE REGION
FOR MORE SHOWERS OVER THE WEEKEND...BUT THE EXACT TIMING IS OFF IN
THE MODELS. THEREFORE LITTLE CHANGES WERE MADE DURING THIS PERIOD
AND WILL MAINTAIN A FORECAST CLOSER TO CLIMO. 33

&&

.HYDROLOGY...THE SYSTEM TONIGHT AND MONDAY IS WET BUT DOES NOT
HAVE ENOUGH RAIN TO CAUSE FLOODING. THE SYSTEM LAST NIGHT BROUGHT AN
INCH PLUS TO THE OLYMPICS...AND THE NEXT ONE WILL BRING PERHAPS
ANOTHER 2 INCHES. THESE WILL SERVE TO PRIME THE PUMP...SO TO SPEAK.
PREVIOUSLY DRY AREAS WILL BECOME WET AND NEARLY EMPTY RIVERS ON THE
OLYMPIC PENINSULA WILL RISE TO WET SEASON LEVELS.

THE GFS AND WRF VERSION OF THE HEAVY RAIN BEGINNING TUESDAY NIGHT IS
PROBABLY ENOUGH TO BRING THE SKOKOMISH RIVER TO FLOOD STAGE. IF THE
OUTLIER EURO SOLUTION IS CORRECT THEN SOME MORE RIVERS ON THE
OLYMPIC PENINSULA SHOULD RISE SIGNIFICANTLY...PERHAPS TO FLOOD
STAGE. MODELS DO CONFINE FLOOD-PRODUCING RAINFALL TO THE OLYMPIC
PENINSULA. ANY FLOODING ON THE SKOKOMISH RIVER WOULD PROBABLY OCCUR
WEDNESDAY NIGHT OR THURSDAY.

&&

.AVIATION...SOUTHERLY FLOW ALOFT. A FRONT WILL REACH THE COAST THIS
AFTERNOON AND MOVE INLAND TONIGHT. AIR MASS STABLE WITH MOSTLY MID
LEVEL MOISTURE OVER THE AREA TODAY. AREAS OF FOG AND LOW CLOUDS AT
THE COAST AND OVER THE SOUTH INTERIOR SHOULD BREAK UP IN THE NEXT
FEW HOURS. LOW LEVELS WILL BECOME MOIST ALL AREAS WITH RAIN
DEVELOPING TONIGHT AS THE FRONT MOVES ONSHORE.

KSEA...MID LEVEL CLOUDS TODAY. THERE IS SOME FOG OVER THE SOUTH
SOUND BUT IT LOOKS LIKE IT WILL STAY SOUTH OF THE TERMINAL. CEILINGS
WILL LOWER WITH RAIN DEVELOPING MONDAY MORNING. SOUTH WIND 4 TO 8
KNOTS. SCHNEIDER

&&

.MARINE...A FRONT WILL BRING GALES TO THE COASTAL WATERS AND SMALL
CRAFT ADVISORY WINDS TO MOST OTHER WATERS TODAY. WINDS WILL EASE A
BIT TONIGHT AS THE FRONT MOVES INLAND.

ANOTHER STRONG FRONT WILL MOVE THROUGH THE WATERS TUESDAY FOLLOWED
BY YET ANOTHER SYSTEM ON WEDNESDAY. EACH OF THESE SYSTEMS WILL BRING
AT LEAST SMALL CRAFT ADVISORY WINDS TO MOST OF THE WATERS. GALES ARE
LIKELY FOR THE COASTAL WATERS AS EACH FRONT MOVES THROUGH. SCHNEIDER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...GALE WARNING COASTAL WATERS AND WEST ENTRANCE STRAIT OF
     JUAN DE FUCA.
    .SMALL CRAFT ADVISORY ALL OTHER WATERS EXCEPT PUGET SOUND AND
     HOOD CANAL.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML




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