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000
FXUS66 KPQR 101044
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
243 AM PST WED FEB 10 2010

.SYNOPSIS...A FRONTAL SYSTEM CROSSING 130W EARLY THIS MORNING WILL
APPROACH THE COAST THIS MORNING AND SPREAD ONSHORE THIS AFTERNOON AND
EVENING...BRINGING RAIN TO SOUTHWEST WASHINGTON AND NORTHWEST OREGON
AND SNOW TO THE HIGHER CASCADES. THE WARM FRONT FROM THE NEXT SYSTEM
MOVES IN TONIGHT AND EARLY THURSDAY...FOLLOWED BY THE RATHER STRONG
COLD FRONT LATE THURSDAY AND THURSDAY NIGHT. THERE IS A POSSIBILITY
OF STRONG WINDS NEAR THE IMMEDIATE COAST JUST AHEAD OF THIS COLD
FRONT LATE THURSDAY AND THURSDAY EVENING. SNOW IS AGAIN EXPECTED IN
THE HIGHER CASCADES TONIGHT AND EARLY THURSDAY...AND AGAIN THURSDAY
NIGHT. PRECIPITATION WILL EASE EARLY FRIDAY THEN INCREASE AGAIN
FRIDAY AFTERNOON AS THE NEXT FRONT MOVES IN. THE NEXT SYSTEM MOVES
MORE INTO WASHINGTON EARLY IN THE WEEKEND...WITH THE TRAILING COLD
FRONT MOVING THROUGH OUR AREA ABOUT SUNDAY. THERE IS AN INDICATION OF
A BIT MORE OF A BREAK BETWEEN SYSTEMS NEXT WEEK.
&&

.SHORT TERM...WE HAVE A LITTLE FOG AROUND EARLY THIS MORNING...BUT
STRATUS HAS FORMED AS THE LOW LEVEL FLOW IS TRYING TO TURN ONSHORE
AHEAD OF THE NEXT SYSTEM. THIS IS WILL LIKELY RESULT IN DECREASING
FOG AS THE CLOUDS BECOME DOMINATE. THEN ATTENTION TURNS TO THE NEXT
FRONT THAT IS CROSSING 130W EARLY THIS MORNING. THE MODELS REMAIN
CONSISTENT ON THIS SYSTEM APPROACHING THE COAST THIS MORNING...THEN
MOVE THE PRECIPITATION ONSHORE THIS AFTERNOON. THE FRONT STALLS OVER
OUR AREA TONIGHT AND TRANSFORMS INTO THE WARM FRONT AHEAD OF THE NEXT
SYSTEM...CURRENTLY OUT BETWEEN 140W AND 150W. THIS WARM FRONT JUICES
UP THE PRECIPITATION TONIGHT...AND DEPENDING ON HOW QUICKLY SNOW
LEVELS RISE...WE COULD NEED A SNOW ADVISORY ABOVE ABOUT 5000 FEET OR
SO. THE WARM FRONT THEN LIFTS NORTH ON THURSDAY BEFORE THE ASSOCIATED
COLD FRONT APPROACHES THE COAST LATE THURSDAY AND MOVES ONSHORE
THURSDAY NIGHT.

THE MODELS SHOW A RATHER STRONG LOW MOVING NORTH ALONG THE FRONT AND
OFF THE COAST LATE THURSDAY AND THURSDAY NIGHT...AND SUGGEST THAT
THIS IS CAPABLE OF PRODUCING HIGH WINDS ALONG THE IMMEDIATE COAST.
WILL ISSUE A HIGH WIND WATCH WITH THIS ISSUANCE.

SNOW LEVELS COME DOWN THURSDAY NIGHT WITH THIS FRONT AND COULD REACH
PASS ELEVATIONS. THERE IS A POSSIBILITY OF ADVISORY AMOUNTS THURSDAY
NIGHT AS WELL...BUT PROBABLY LOW END.

PRECIPITATION EASES LATE THURSDAY NIGHT AND EARLY FRIDAY BEHIND THE
THURSDAY NIGHT SYSTEM...BUT ANOTHER FRONT WILL COME ONSHORE FRIDAY
AFTERNOON FOR MORE RAIN AND MOUNTAIN SNOW. THIS MIGHT MAKE A DENT IN
THE SNOWPACK BUT THAT IS PROBABLY ALL...BUT STILL SHOULD HELP.
TOLLESON

.LONG TERM...THE MODELS ARE INDICATING THAT THE NEXT FRONT WILL LIFT
A BIT NORTH FOR EARLY IN THE WEEKEND...AND POSSIBLY A LULL IN THE
PRECIPITATION. THE ASSOCIATED COLD FRONT WILL PROBABLY COME THROUGH
ON SUNDAY. THE MEDIUM RANGE MODELS ARE INDICATING THAT THE FLOW OVER
THE EASTERN PACIFIC WILL BECOME MORE AMPLIFIED NEXT WEEK...AND THIS
WILL SLOW DOWN SYSTEMS AND POSSIBLY GIVE US SOME DRY PERIODS IN
BETWEEN SYSTEMS. HAVE NOT MADE ANY CHANGES THIS MORNING...BUT IF THE
MODEL TRENDS REMAIN CONSISTENT...WE WILL NEED TO DRY OUT THE FORECAST
FOR SOME PERIODS NEXT WEEK. TOLLESON
&&

.AVIATION...WEAK SOUTHWEST ONSHORE PUSH AHEAD OF APPROACHING WARM
FRONT BRINGING MVFR CIGS TO THE COAST AND SOUTH INLAND AREAS THIS
MORNING. PATCHY DENSE FOG FORMED ELSEWHERE. THICKER CLOUDS
ARRIVING 12Z COAST AND 15Z INLAND WILL LIMIT OR EVEN BEGIN
DISSIPATING THE FOG. OTHERWISE...EXPECT RAIN BEGINNING AROUND 18Z
AND CONTINUING THROUGH WED NIGHT WITH MVFR AT TIMES ESPECIALLY
ON THE COAST.

KPDX AND APPROACHES...MIX OF MVFR AND IFR CIGS BUT LOWER CHANCES
FOR IFR VIS SINCE STRATUS HAS DEVELOPED AND THICKER HIGHER CLOUDS
ARRIVING IN THE MORNING.
&&

.MARINE...WARM FRONT SYSTEM MOVES OVER THE WATERS BRINGING MARGINAL
GALES BY TODAY AND STRONGER GALES BY THU AFTERNOON. SEAS WILL ALSO
BE BUILDING ABOVE 10 FT TODAY AND CLOSER TO 15 FEET THU. ADDITIONAL
FRONTAL SYSTEMS WILL TRACK INTO THE AREA FRI AND SAT CONTINUING A
MORE ACTIVE WEATHER PATTERN.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WATCH FOR THE NORTH AND CENTRAL OREGON COASTS FROM
     MID THURSDAY AFTERNOON UNTIL AFTER MIDNIGHT THURSDAY NIGHT.
WA...HIGH WIND WATCH FOR THE SOUTH WASHINGTON COAST FROM MID
     THURSDAY AFTERNOON UNTIL AFTER MIDNIGHT THURSDAY NIGHT.
PZ...GALE WARNING FROM 2 PM THIS AFTERNOON TO 10 PM PST THURSDAY
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
     OUT TO 60 NM.

&&

$$

MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.