FXUS66 KPQR 010434
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
830 PM PST MON NOV 30 2009

.SYNOPSIS...A WEAK AND DYING FRONT WILL CONTINUE TO PUSH SOUTHWARD 
ACROSS THE AREA TONIGHT WITH SOME PATCHY LIGHT DRIZZLE POSSIBLE IN 
THE CASCADES. AN UPPER LEVEL RIDGE BUILDING OFFSHORE WILL EASE INTO 
WESTERN WASHINGTON AND OREGON LATE TUESDAY AND WEDNESDAY. THIS WILL 
KEEP THE AREA DRY WITH INLAND VALLEY INVERSIONS CONTINUING RESULTING 
IN SOME FOG AND LOW CLOUDS. OFFSHORE WILL BEGIN TO INCREASE TUESDAY 
AS COOL AIR SETTLES EAST OF THE CASCADES.  STRONG EAST WINDS AND 
COLDER TEMPERATURES MAY ARRIVE THIS WEEKEND AS HIGH PRESSURE MOVES 
EAST OF THE CASCADES.

&&

.SHORT TERM...A WEAK AND DYING FRONT WILL CONTINUE TO SLIDE SOUTHWARD
ACROSS THE AREA TONIGHT WITH SOME POSSIBLE DRIZZLE GETTING SQUEEZED
OUT IN THE NORTH CASCADES. OTHERWISE...STRATUS AND FOG WILL CONTINUE
TO BLANKET MOST OF THE VALLEY LOCATIONS OVERNIGHT. 

THE UPPER LEVEL RIDGE WILL REBOUND OVER THE EASTERN PACIFIC AND EASE 
INTO WESTERN WA AND OREGON TUES AND WED. AT THE SURFACE...STRONGER 
HIGH PRESSURE WILL ALSO SLIDE INTO THE NORTHERN ROCKIES TUE AND WED 
RESULTING IN INCREASING EASTERLY WINDS CROSSING THE CASCADES AND 
THROUGH THE COLUMBIA RIVER GORGE. THIS SHOULD BRING ENOUGH MIXING AND
DRYING IN THE NORTHERN WILLAMETTE VALLEY NEXT COUPLE OF DAYS TO LIMIT
FOG FORMATION. THE UPPER LEVEL RIDGE MAINTAINS ITS HOLD INTO THU FOR 
CONTINUED DRY AND COOL WEATHER WITH SOME FOG AND STRATUS IN THE 
VALLEYS THROUGH AT LEAST MID WEEK. TW

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
12Z ECMWF AND GFS OPERATIONAL RUNS CONTINUE TO SHOW DISTINCTLY 
DIFFERENT SOLUTIONS THAT PERSIST THROUGH THE EXTENDED PERIOD. 
LOOKING OVER SPAGHETTI CHARTS FOR GFS ECMWF AND CANADIAN LENDS 
SUPPORT TO BOTH TYPES OF SOLUTIONS...EITHER A TROUGH INLAND WITH A 
RIDGE OFFSHORE...OR A CUTOFF LOW LINGERING OVER THE PACNW. GIVEN 
CONTINUED UNCERTAINTY...WILL MAKE LITTLE CHANGE TO FORECAST FOR THE 
TIME BEING.

&&

.AVIATION...INLAND...EXPECT WIDESPREAD IFR TO LIFR CIGS 
OVERNIGHT...WITH AREAS OF 1/4SM VSBY AND FOG SCATTERED THROUGHOUT 
THE VALLEY. KPDX AND KTTD WILL LIKELY BE THE LAST PLACES TO GO DOWN 
TO LIFR LEVELS. AT THE COAST...KAST WILL WAFFLE BETWEEN MVFR AND VFR 
THROUGH 08Z...THEN QUICKLY DROP TO LIFR CONDITIONS AS LOW STRATUS 
AND FOG DEVELOP. EXPECT LIFR FOG AND STRATUS TO DEVELOP AT KONP BY 
06-08Z. OFFSHORE FLOW BEGINS TO DEVELOP AFTER 12Z TUE...AND WILL HELP
COASTAL AND NORTHERN INLAND SITES IMPROVE TO VFR BY 21Z. KSLE AND
KEUG WILL HOLD ON TO IFR OR LIFR STRATUS THROUGH 00Z TUE AFTERNOON.

KPDX AND APPROACHES...CIGS OVC008-010 WILL GRADUALLY DROP TO LIFR 
LEVELS BY 09Z TONIGHT. PERIODS OF IFR VSBY AFTER 12Z ALSO 
POSSIBLE...BUT GUIDANCE LESS CLEAR ON THAT. ABOUT 60 PERCENT 
POSITIVE IN IFR VSBY RESTRICTIONS AFTER 12Z. EAST WINDS SHOULD 
DEVELOP AROUND 18Z FOR GRADUAL IMPROVEMENT TO VFR CONDITIONS BY 
21Z.  

.MARINE...SEAS ALREADY DROPPING TO 9 FT THIS EVENING...AND WITH BUOY 
46036 HAVING DROPPED TO 9 FT AS WELL...WILL END THE SCA FOR 
HAZARDOUS SEAS WITH THE EVENING PACKAGE. DUE TO WANING SEAS...WILL 
ALSO LIMIT SCA FOR ROUGH COLUMBIA BAR TO THE UPCOMING EBB TIMES AT 
330 AM AND 345 PM TUE. OTHERWISE...NO SIGNIFICANT CHANGES TO THE 
FORECAST. WINDS GRADUALLY TURN OFFSHORE TOMORROW AND STRENGTHEN AS 
THEY DO SO. WINDS SHOULD STAY BELOW ADVISORY LEVELS BUT WILL SEE 
GUSTS TO 20KT AS THE WINDS VEER FROM NORTH TO NORTHEAST TOMORROW 
AFTERNOON...ESPECIALLY NEAR COASTAL GAPS. ANOTHER WEAK FRONT WILL 
ENTER THE WATERS ON THU FOR SEAS AROUND 10FT...FOLLOWED BY NEAR 
SMALL CRAFT NORTHERLIES AFTER FRONTAL PASSAGE THU EVENING.    DALTON

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY ROUGH COLUMBIA RIVER BAR EARLY TUE MORNING 
      AND AGAIN TUE AFTERNOON.

&&

$$

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.