Strong Wind in Washington, September 29, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
ISSUED BY NWS PORTLAND OR
900 AM PDT THU SEP 29 2005

.SYNOPSIS...A FRONTAL SYSTEM WILL BRING PERIODS OF RAIN TO THE
ENTIRE AREA TODAY AND TONIGHT...LINGERING IN THE SOUTH ON FRIDAY.
COOLER AIR WILL SLOWLY FILTER IN FROM THE NORTH LATE TONIGHT AND
FRIDAY AS THE FRONT SLOWLY SAGS SOUTH...DROPPING SNOW LEVELS TO
AROUND 5000 FEET. COOL AND SHOWERY WEATHER WILL FOLLOW THE FRONT IN
ALL BUT THE SOUTH ON FRIDAY...AND OVER ALL OF THE AREA SATURDAY. AN
UNSETTLED PATTERN WILL CONTINUE THIS WEEKEND AND EARLY NEXT WEEK AS
AN UPPER LOW REMAINS ALONG THE COAST.
&&

.SHORT TERM...LATEST SATELLITE IMAGERY SHOWS A LONG FETCH OF
MOISTURE OVER THE EASTERN PACIFIC CONTINUES TO AIM DIRECTLY INTO
SOUTHERN B.C. AND NORTHERN WASHINGTON THIS MORNING. SATELLITE PWS
ARE 1.75 TO 2 INCH PWS OFFSHORE SUPPORTING THE INCREASING ECHOES ON
NATIONAL WEATHER SERVICE DOPPLER RADAR FROM SOUTHERN B.C. COAST INTO
THE OLYMPICS. WATER VAPOR IMAGERY SHOWS FIRST GOOD WAVE OFFSHORE
WILL PUSH THROUGH THIS AFTERNOON AND TONIGHT...AND THIS INITIAL WAVE
PUSHES THE TRAILING COLD FRONT SOUTH THROUGH THE NIGHT TONIGHT. BUT
IT APPEARS THE RAIN WILL SLOPE BACK INTO THE COLD AIR CONTINUE MOST
OF THE AREA OVERNIGHT TONIGHT. MODELS NOW SHOWING ANOTHER WAVE BACK
AROUND 160W IN THE WATER VAPOR IMAGERY WILL COME THROUGH ON FRIDAY.
THIS LOOKS LIKE IT WILL STALL THE FRONT IN THE SOUTHERN PARTS OF THE
AREA ON FRIDAY BEFORE FINALLY CLEARING ALL OF THE FORECAST AREA
FRIDAY EVENING.

IN THE INTERIM...SHOULD SEE AMPLE RAINFALL AMOUNTS NOT SEEN IN A
WHILE ESPECIALLY IN THE SOUTHWEST FACING SLOPES OF THE OLYMPICS AND
THE CASCADES...BUT EVEN LOW LANDS SHOULD DO OK QPF WISE.

BEHIND THE FRONT PRECIP SHOULD DIMINISH TO JUST SCATTERED SHOWERS...
BUT COULD BE IN THE FORM OF SNOW SHOWERS IN THE MOUNTAINS AS SNOW
LEVELS PLUMMET TO AROUND 5000 FEET.  LOCAL ACCUMULATIONS OF A FEW
INCHES NOT OUT OF THE QUESTION BY SAT MORNING. A POST FRONTAL
SHOWERY PATTERN CONTINUES SAT INTO SUN. AS AN UPPER LOW SETS UP OFF
THE COAST SUNDAY THE CURRENT MODELS ARE SHOWING MORE ORGANIZATION TO
THE SHOWERS COMING IN SUNDAY. MAY NEED TO BUMP POPS UP TO LIKELY
CATEGORY. TEMPS WILL BE NOTICEABLY COOLER WITH SOME AREAS NOT
GETTING OUT OF THE 50S. ONE OTHER THING OF INTEREST IS THE
INSTABILITY WITH THE COLD POOL ALOFT. MODELS GENERATE SOME WEAK CAPE
AND LIS 0 TO -2 SAT AFTERNOON AND SUN. ISOLATED LIGHTNING APPEARS
POSSIBLE BUT TOO MARGINAL TO CALL AT THIS POINT. JUST SOMETHING TO
KEEP IN MIND AS WE GET CLOSER TO THE WEEKEND.

THE UPPER TROUGH AXIS MOVES EAST OF WASHINGTON BY TUE WITH A
DECREASE IN SHOWER ACTIVITY. THE GFS SHOWS THE NEXT SYSTEM NOT FAR
BEHIND...AND BRINGS WARM FRONTAL MOISTURE TO THE COAST TUESDAY NIGHT
AND WEDNESDAY. THE PATTERN THEREAFTER BECOMES UNCERTAIN WITH THE
FLOW MAYBE LIFTING N FOR A DRY WED OR A TROUGH MOVING BY.  CERTAINLY
SOME CHANCE OF RAIN IN THIS PATTERN...SO NO CHANGE MADE TO THE
EXTENDED. TOLLESON
&&

.AVIATION...WARM FRONT PRECIP HAS SPREAD OVER MORE OF THE AREA THIS
MORNING. CIGS MOSTLY MVFR INLAND AND IFR ONE THE COAST. S GRADIENTS
ARE COMING UP NICELY WITH WINDS IN THE TEENS AND LOCALLY ABOVE 20
KT. PT
&&

.SEW WATCHES/WARNING/ADVISORIES
.WA...GALE WARNING COAST JAMES ISLAND TO CAPE FLATTERY
      SMALL CRAFT ADVISORY REMAINDER OF WATERS

&&

.KATX...VCP21/CSR21 OPERATIONAL. DATA MISSING AT TIMES DUE TO AWIPS
UPGRADE

&&