Weather Service Report


598 
FXUS66 KSEW 240503
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
1000 PM PDT THU OCT 23 2014

.SYNOPSIS...AN UPPER TROUGH WILL GIVE WAY TO WEAK HIGH PRESSURE 
FRIDAY. A WARM FRONT WILL BRING SOME RAIN BACK TO THE AREA FRIDAY 
NIGHT AND SATURDAY. A LOW PRESSURE SYSTEM WILL BRING RAIN AND WINDY 
CONDITIONS TO THE AREA SATURDAY NIGHT. A SERIES OF SYSTEMS WILL KEEP 
THE WEATHER WET AND BREEZY AT TIMES NEXT WEEK.

&&

.SHORT TERM....THAT LINE OF SHOWERS AND ISOLATED TSTMS MOVING ONTO 
THE SOUTH WA COAST AT 10PM IS HOLDING TOGETHER...SO IT WILL LIKELY 
REACH THE CENTRAL AND THEN THE NORTH WA COAST OVER THE NEXT SEVERAL 
HOURS...FORECASTS UPDATED FOR THAT. BUT FOR THE INTERIOR THE 
SCATTERED SHOWERS SHOULD END OVERNIGHT. FRIDAY WILL BE A DRY DAY AS 
A LITTLE UPPER RIDGING AND OFFSHORE FLOW DEVELOP OVER THE AREA. THE 
NEXT SYSTEM WILL HAVE A WARM FRONT DRAPED FROM A DEEP LOW CENTER OFF 
NRN CALIF LATE FRIDAY...ACROSS NW OREGON AND ALONG THE WA/ORE 
BORDER. THE FRONT MOVES NORTH OVERNIGHT FRIDAY NIGHT AND SHOULD BE 
INTO VANCOUVER ISLAND AND SW B.C. BY MIDDAY SAT. THE NAM SHOWS THAT 
THE LOW PRESSURE AREA GETS STRETCHED OUT ALONG THE WA AND ORE 
COASTAL WATERS BY THAT TIME AS PRECIP FILLS IN OVER MOST OF WRN WA. 
THE SURFACE LOW WILL MOVE TO THE INTERIOR OF WRN WA SATURDAY EVENING 
AND GIVE BLUSTERY CONDITIONS IN STRONG ONSHORE FLOW. SUNDAY LOOKS 
LIKE A COOL DAY WITH SCATTERED SHOWERS AND PERHAPS A PSCZ...SHOWERS 
LIKELY IN THE MOUNTAINS...AND A SNOW LEVEL NEAR PASS LEVEL.

.LONG TERM...AFTER A BRIEF LULL IN PRECIPITATION ON MONDAY...ANOTHER 
LOW WILL MOVE INLAND OVER VANCOUVER ISLAND ON TUESDAY BRINGING WET 
AND POSSIBLY BREEZY WEATHER TO THE AREA. WET AND LOCALLY BREEZY 
CONDITIONS IS EXPECTED TO CONTINUE WEDNESDAY AND THURSDAY AS YET 
MORE FEATURES MOVE INTO THE AREA. 

&&

.HYDROLOGY...PERIODS OF RAIN ARE EXPECTED OVER THE NEXT SEVERAL 
DAYS...BUT RAINFALL AMOUNTS ARE NOT EXPECTED TO BE HYDROLOGICALLY 
SIGNIFICANT. THE SKOKOMISH RIVER IN MASON COUNTY FELL BELOW FLOOD 
STAGE THIS EVENING.

&&

.AVIATION...STRONG SOUTHWESTERLY FLOW TONIGHT WEAKENING ON FRIDAY. 
AIR MASS REMAINING UNSTABLE OVERNIGHT THEN STABILIZING FRIDAY 
MORNING. WARM FRONT MOVING UP FROM THE SOUTH FRIDAY NIGHT.

CEILINGS AOA 10000 FEET. THE EXCEPTION TO THIS WILL BE OVER THE NEXT 
THREE HOURS AS ONE LAST BAND OF SHOWERS APPROACHING THE COAST AT 05Z 
MOVES THROUGH THE AREA. CEILINGS LOWERING TO NEAR 4000 FEET IN THE 
SHOWERS. BAND WILL BE THROUGH THE AREA BY 09Z. BETWEEN 10Z-16Z 
ISOLATED VISIBILITIES 1-3SM WITH CEILINGS BELOW 500 FEET ALONG THE 
I-5 CORRIDOR FROM ABOUT KOLM SOUTHWARD. 

KSEA...BAND OF SHOWERS MOVING THROUGH AROUND 06Z TO 09Z WITH 
CEILINGS LOWERING TO NEAR 5000 FEET. OUTSIDE OF THAT WINDOW CEILINGS 
AOA 10000 FEET. SOUTHERLY WINDS 4 TO 8 KNOTS BECOMING SOUTHEAST 
EARLY FRIDAY MORNING THEN NORTHEAST FRIDAY AFTERNOON. FELTON 

&&

.MARINE...THE FLOW WILL WEAKEN AND BECOME MORE EASTERLY OVERNIGHT 
DUE TO FALLING PRES OVER THE EASTERN PACIFIC. OFFSHORE FLOW WILL 
PREVAIL ON FRIDAY AND WILL GRADUALLY STRENGTHEN IN RESPONSE TO A 992 
MB LOW APPROACHING FROM THE SW. THIS LOW IS EXPECTED TO WEAKEN TO 
996 MB AS IT MOVES ACROSS THE WASHINGTON COASTAL WATERS ON SATURDAY. 
GALE FORCE WINDS ARE POSSIBLE OVER PARTS OF THE AREA SATURDAY AHEAD 
OF AND BEHIND THE COLD OR OCCLUDED FRONT.

THERE CONTINUES TO BE SOME UNCERTAINTY IN REGARDS TO THE TRACK AND 
STRENGTH OF THE LOW SATURDAY. THERE IS A POSSIBILITY OF GALE FORCE 
WINDS OVER MUCH OF THE WATERS...IF THE NE MOVING LOW MOVES INTO FAR 
SW BRITISH COLUMBIA. IF IT MOVES INTO NORTHERN OREGON OR TRACKS 
ACROSS FAR SW WASHINGTON...THE THREAT OF GALE FORCE WINDS WILL BE 
CONFINED TO A SMALL AREA. THE CURRENT FORECAST REFLECTS MODEL 
CONSENSUS. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH RIVER IN
     MASON COUNTY.

PZ...GALE WATCH IN EFFECT FOR THE COASTAL WATERS FROM SATURDAY       
     MORNING THROUGH SATURDAY AFTERNOON.

&&

$$

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