FXUS66 KPQR 160436
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
833 PM PST TUE DEC 15 2009

.SYNOPSIS...WET WEATHER WILL CONTINUE FOR THE NEXT FEW DAYS AS THE
JET STREAM TAKES AIM AT THE PACIFIC NORTHWEST. A FRONTAL BAND WILL
CONTINUE TO GIVE SOLID RAIN TO THE CASCADES TONIGHT...WITH SNOW ABOVE
6000 FEET. WE MAY SEE A BIT OF A BREAK IN THE RAIN LATE TONIGHT AND
EARLY WED MORNING AS WE WAIT IN BETWEEN SYSTEMS. THIS BREAK WILL BE 
SHORT LIVED AS SHOWERS RETURN WED AFTERNOON AND EVENING. ANOTHER 
FRONT IS DUE IN ON THU FOR MORE WET WEATHER. &&

.SHORT TERM...SATELLITE IMAGERY SHOWS A SURFACE LOW MOVING TOWARD THE
QUEEN CHARLOTTE ISLANDS THIS EVENING...WITH AN ASSOCIATED OCCLUDED 
FRONT OVER THE INTERIOR. WINDS HAVE EASED BELOW HIGH WIND CRITERIA 
ALONG THE COAST AND SHOULD REMAIN SO OVERNIGHT. 

WE MAY SEE A BREAK FROM SIGNIFICANT RAIN TONIGHT AND EARLY WEDNESDAY 
MORNING...ESPECIALLY WEST OF THE CASCADES...AND THIS WILL BE 
REFLECTED IN THE UPDATED EVENING GRID PACKAGE. ANY RAIN THAT DOES 
FALL WILL BE IN THE LIQUID FORM...WITH THE POSSIBLE EXCEPTION OF 
AREAS NEAR HOOD RIVER AND IN THE HOOD RIVER VALLEY UNTIL MIDNIGHT. NO
ADVISORIES WILL BE NEEDED.   

ANOTHER DISTURBANCE WILL MOVE INTO THE AREA BY WED AFTERNOON FOR 
INCREASED PRECIP CHANCES. THIS WILL BE FOLLOWED BY POST FRONTAL 
SHOWERS WED EVENING...AND ANOTHER FRONT ON THURSDAY. NEEDLESS TO SAY 
THE REST OF THE WEEK WILL BE WET. FORTUNATELY NONE OF THE FRONTS LOOK
EXCEPTIONALLY WET...SO NO FLOODING THREATS SEEM IMMINENT...AND SNOW 
LEVELS WILL REMAIN ON THE HIGH SIDE SO LOW ELEVATION SNOW WILL ALSO 
NOT BE A PROBLEM ANYWHERE.

.LONG TERM....WET WEATHER PERSISTS THROUGH THE EXTENDED PERIOD. AN 
UPPER LEVEL TROUGH PUSHES A RIDGE EASTWARD...ALLOWING PRECIP TO 
ENVELOP THE CWA BY LATE FRI. MODELS DISAGREE ON THE TIMING AND 
IMPACTED AREAS OF A BRIEF BREAK SOMETIME SAT. GFS SHOWS MUCH OF THE 
CWA UNDER A WEAK RIDGE SAT AFTERNOON...ECMWF SHOWS SOUTHERN OREGON 
ENJOYING THIS BREAK INSTEAD. ANOTHER STRONG UPPER LOW SPINS OFF THE 
COAST EARLY SUN...MAKING LANDFALL AROUND MON. SEVERAL SYSTEMS FOLLOW 
BY EARLY NEXT WEEK. THESE SYSTEMS ARE LADEN WITH MOISTURE...AND AT 
TIMES MAY BRING HEAVY RAINFALL AND WINDY CONDITIONS TO THE PAC NW. 
SNOW LEVELS SHOULD RISE TO NEAR 8000 FT THROUGH THE WEEKEND...BUT 
STEADILY FALL ONCE AGAIN BY NEXT WEEK. LRAMIREZ

&&

.AVIATION...MVFR TO IFR SHOULD CONTINUE ON THE COAST THROUGH WED. 
INLAND...MOSTLY MVFR NORTH OF KSLE WITH AREAS OF IFR TOWADS THE 
COAST WHILE MAINLY VFR SOUTH OF KSLE. SOME IMPROVEMENT MAY OCCUR 
AFTER 08Z AS AFRONT MOVES THROUGH. NEXT TROUGH ARRIVES LATER WED 
MORNING AND AFTERNOON...BRINGING PRIMARILY MVFR CONDITIONS NORTH OF 
KSLE.

.KPDX AND APPROACHES...PREDOMINANTLY MVFR THROUGH WED. VFR A 
POSSIBILITY DURING THE MORNING BEFORE THE NEXT TROUGH ARRIVES LATE 
MORNING AND EARLY AFTERNOON.

&&

.MARINE...WINDS HAVE EASED A LITTLE BELOW GALE AS A FRONT MOVES 
ASHORE.  BUT WINDS TO RETURN TO GALES AS A SURFACE TROUGH ROTATES 
TOWARD THE NORTH COAST LATER THIS EVENING AND CONTINUE THROUGH WED 
MORNING BEFORE EASING.COMBINED SEAS 13 TO 15 FT TONIGHT WILL 
INCREASE AS LARGER SWELL ARRIVES WED. SEAS WILL PEAK AROUND 20 FEET 
WED EVENING AND REMAIN IN THE UPPER TEENS INTO THU MORNING.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR/WA...GALE WARNING UNTIL 10 AM PST WEDNESDAY FOR COASTAL     
 WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR
 CONDITIONS THROUGH WED.
&&

$$

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.