Flood Watch 3, NWS Seattle, WA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
341 AM PST SAT FEB 15 2014

.SYNOPSIS...A SERIES OF STRONG PACIFIC STORMS WILL IMPACT THE REGION
THROUGH SUNDAY. THE FIRST SYSTEM WILL ARRIVE TODAY AND BRING STRONG
WINDS TO THE COAST AND NORTHWEST INTERIOR AS WELL AS LOCALLY HEAVY
SNOW IN THE MOUNTAINS. THE NEXT SYSTEM WILL AFFECT THE AREA ON
SUNDAY AND IS EXPECTED TO BE STRONGER. ANTICIPATE WINDY CONDITIONS
ACROSS MUCH OF THE AREA...ESPECIALLY OVER THE COAST AND NORTHWEST
INTERIOR. THE CASCADES WILL RECEIVE SIGNIFICANT SNOWFALL FROM THIS
SYSTEM.

&&

.SHORT TERM...
A VIGOROUS PACIFIC STORM OFFSHORE WILL BRING A PERIOD OF HEAVY SNOW
TO THE CASCADES AND STRONG...GUSTY WINDS ACROSS THE LOWLANDS...
PARTICULARLY OVER THE COAST AND NORTHWEST INTERIOR TODAY. THE MODELS
BACKED OFF ON THE SPEEDS WITH THIS SYSTEM...SO THE HIGH WIND WATCH
WAS REPLACED WITH A HIGH-END WIND ADVISORY. THE STRONGEST WINDS WILL
LIKELY BE NEAR THE WATER AS OPPOSED TO FARTHER INLAND BUT WINDY
CONDITIONS ARE EXPECTED NEARLY EVERYWHERE.

THE HEAVIEST SNOW WILL LIKELY FALL ON MOUNT RAINIER AND MOUNT
BAKER...WHERE STRONG UPSLOPE OR SOUTHWEST FLOW WILL ENHANCE SNOWFALL
RATES. LESSER AMOUNTS WILL FALL IN THE LOWER PASSES SUCH AS
SNOQUALMIE AND STEVENS DUE TO SHADOWING.

QUITE A BIT OF COLD AIR WILL FOLLOW THE FRONT TONIGHT AND SNOW
LEVELS WILL PLUMMET TO NEAR 1K FT. THUS...CANNOT RULE OUT SOME WET
SNOW ON THE HIGHER HILLS LATE TONIGHT THROUGH EARLY SUNDAY MORNING.
AT THIS TIME...ONLY A DUSTING IS EXPECTED. THE CONVECTIVE APPEARANCE
OF THE CLOUDS BEHIND THE FRONT SUGGESTED THE POTENTIAL FOR TSTMS
OVER THE COASTAL WATERS TONIGHT. ALSO...CANNOT RULE OUT A RANDOM
STRIKE ELSEWHERE.

ANOTHER STRONG STORM WILL IMPACT THE REGION ON SUNDAY. THIS SYSTEM
APPEARED STRONGER AND WETTER THAN THE SYSTEM THAT WILL IMPACT THE
CWA TODAY. WENT ON AHEAD AND ISSUED A HIGH WIND WATCH FOR THE COAST
AND NORTHWEST INTERIOR FOR SUNDAY. ELSEWHERE...EXPECT WIND ADVISORY
SPEEDS...ESPECIALLY ACROSS THE PUGET SOUND REGION.

THE CASCADES IS EXPECTED TO RECEIVE 1 TO 3 FEET OF SNOW FROM THE
SUNDAY SYSTEM...WITH THE HEAVIEST AMOUNTS FALLING ON MOUNT BAKER AND
MOUNT RAINIER...WHERE 50-60 KNOT SOUTHWEST FLOW WILL ENHANCE
SNOWFALL RATES ON THE SOUTHWEST FACING SLOPES.

THE SKOKOMISH RIVER IS EXPECTED TO EXPERIENCE MINOR FLOODING SUNDAY
NIGHT...SO A FLOOD WATCH WAS ISSUED FOR THIS RIVER.

.LONG TERM...
NO CHANGES TO THE INHERITED FORECAST. A CHILLY...WET PATTERN WILL
PREVAIL DURING MUCH OF THIS PERIOD. THE MOUNTAINS CAN EXPECT LOCALLY
HEAVY SNOW AT TIMES...ESPECIALLY WITH THE TUE SYSTEM. CANNOT RULE
OUT THE POTENTIAL FOR LOWLAND SNOW EITHER...ESPECIALLY WHERE
CONVECTIVE BANDS DEVELOP. THE MEDIUM RANGE SOLUTIONS WERE HINTING AT
A DRYING TREND BEGINNING LATE IN THE PERIOD AS AN UPPER RIDGE BUILDS
OVER THE PACIFIC NORTHWEST.

&&

.HYDROLOGY...
THE SYSTEMS THAT WILL MOVE ACROSS THE AREA WILL BE FAST-MOVING AND
SNOW LEVELS WILL BE RATHER LOW...ALTHOUGH THE SNOW LEVEL WILL
BRIEFLY RISE TO 4500 TO 5500 FT ACROSS MUCH OF THE CWA TODAY BEFORE
PLUNGING TO NEAR 1K FT EARLY SUNDAY. FLOODING IS NOT EXPECTED WITH
THIS SYSTEM.

THERE IS A CHANCE OF MINOR FLOODING ON THE SKOKOMISH RIVER SUNDAY
NIGHT. RAINFALL AMOUNTS OF 2 TO 3.5 INCHES ARE EXPECTED IN THIS
BASIN DURING THE 24-HR PERIOD ENDING AT 4 AM PST MON...THUS A FLOOD
WATCH WAS ISSUED.

BEYOND SUNDAY...NOT EXPECTING ANY FLOODING ON AREA RIVERS BUT WILL
NEED TO WATCH THE LOWER PORTION OF CHEHALIS RIVER ON MON.

&&

.AVIATION...SOUTHWESTERLY FLOW ALOFT BECOMING STRONG THIS AFTERNOON
INTO THE EVENING HOURS. AIR MASS STABLE WITH INCREASING MOISTURE.

FRONTAL SYSTEM OVER OREGON THIS MORNING WILL SLOWLY MOVE NORTH
MOVING THROUGH WESTERN WASHINGTON IN THE LATE AFTERNOON AND EVENING
HOURS. SOME PATCHY FOG OVER THE SOUTHWEST INTERIOR AND COAST WILL
DISSIPATE EARLY THIS MORNING. JUST SOME HIGH CLOUDS OVER THE AREA
FROM ABOUT KPAE SOUTHWARD WITH A 3500 TO 5000 FOOT DECK TO THE
NORTH. MID LEVEL CLOUDS CLOUDS INCREASING LATE MORNING WITH CEILINGS
LOWERING DOWN TO AROUND 4000 FEET AHEAD OF THE FRONT. COULD SEE SOME
CEILINGS IN THE 2000 TO 3000 FOOT RANGE WITH THE FRONTAL PASSAGE
BETWEEN 00Z-06Z SUNDAY.

KSEA...JUST SOME HIGH CLOUDS THIS MORNING. CEILINGS LOWERING DOWN TO
NEAR 4000 FEET AROUND 21Z WITH RAIN DEVELOPING. POSSIBLE CEILINGS
2000-3000 FEET WITH FRONTAL PASSAGE AROUND 03Z. EASTERLY WINDS 6 TO
10 KNOTS UNTIL MID AFTERNOON. WINDS BECOMING SOUTHEASTERLY MID
AFTERNOON AND THEN SOUTHERLY 15-20 KNOTS WITH GUSTS TO 30 KNOTS
BEHIND THE FRONT THIS EVENING. FELTON

&&

.MARINE...STRONG FRONT ASSOCIATED WITH 980 MB LOW MOVING INLAND JUST
NORTH OF VANCOUVER ISLAND MOVING THROUGH THE WATERS TODAY WITH
GALE FORCE WINDS EXPECTED OVER ALL THE WATERS. WINDS EASING A LITTLE
SUNDAY MORNING THEN INCREASING AGAIN SUNDAY AFTERNOON WITH THE NEXT
SYSTEM REACHING THE AREA. GALES POSSIBLE OVER MOST OF THE WATERS
WITH THIS SYSTEM AS WELL. COMBINED SEAS ALONG THE COAST APPROACHING
20 FEET WITH THE FRONT ON SUNDAY. NEXT SYSTEM IN THIS SERIES
ARRIVING ON TUESDAY LOOKS WEAKER THAN THE WEEKEND SYSTEMS AT THIS
POINT. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WINTER STORM WARNING IN EFFECT FROM NOON TODAY TIL 6 AM PST
     SUNDAY FOR THE CASCADES.

     WIND ADVISORY IN EFFECT THIS AFTERNOON THROUGH TONIGHT FOR
     THE COAST AND NORTHWEST INTERIOR.

     WINTER WEATHER ADVISORY IN EFFECT FROM NOON TODAY TIL 6 AM PST
     SUNDAY FOR  THE OLYMPICS.

     HIGH WIND WATCH IN EFFECT FROM SUNDAY AFTERNOON THROUGH SUNDAY
     EVENING FOR THE COAST AND NORTHWEST INTERIOR.

     WINTER STORM WATCH IN EFFECT FROM SUNDAY MORNING THROUGH LATE
     SUNDAY NIGHT FOR THE CASCADES.

     FLOOD WATCH IN EFFECT FROM SUNDAY EVENING THROUGH LATE SUNDAY
     FOR THE SKOKOMISH RIVER IN MASON COUNTY.

PZ...GALE WARNING IN EFFECT FOR ALL WATERS.

     SMALL CRAFT ADVISORY IN EFFECT FOR ROUGH BAR UNTIL 4 AM PST
     SUNDAY FOR THE GRAYS HARBOR BAR.

&&

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