FXUS66 KPQR 061055
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
255 AM PST SUN DEC  6 2009

.SYNOPSIS...A COLD UPPER TROUGH WILL DROP SOUTH THROUGH THE PACIFIC
NORTHWEST TODAY...BRINGING COLDER ARCTIC AIR AND GUSTY NORTHEAST
WINDS INTO THE AREA TODAY THROUGH MONDAY. ISOLATED SNOW SHOWERS ARE
POSSIBLE TODAY BUT NO ACCUMULATIONS ARE EXPECTED. COLD WEATHER WILL
LIKELY PERSIST THROUGH THE FIRST HALF OF THE WEEK. 

&&

.SHORT TERM...SOME FLURRIES POSSIBLE THIS MORNING BUT SHOULD BE
LIMITED TO SOUTHERN PARTS BY AFTERNOON AS A COLD UPPER LOW DROPS S
THROUGH THE PAC NW. OFFSHORE GRADIENTS WILL INCREASE TODAY AS ARCTIC
AIR WHICH HAS PUSHED S THROUGH EASTERN WA SHIFTS W THROUGH THE GORGE.
IN ADDITION MODELS SHOW 40-50 KT EASTERLY FLOW ALOFT FROM 925MB
THROUGH 850MB TODAY AND TONIGHT WHICH WILL PRODUCE GUSTY RIDGE
WINDS.SOME OF THE WINDS ALOFT MAY SURFACE AT TIMES...BUT MODELS STILL
SUGGEST THE STRONGER WIND GUSTS SHOULD NOT REACH TO THE VALLEYS. THUS
WILL HOLD OFF ON ANY VALLEY WIND ADVISORIES. NAM AND GFS SHOW THE E
WINDS DECREASING LATER MON THROUGH TUE...ALTHOUGH IT WILL REMAIN
QUITE GUSTY NEAR THE W GORGE.
 
THE COLDER ARCTIC AIR WILL ARRIVE TODAY AND TONIGHT AS THE UPPER LOW
DIGS S OF THE REGION INTO NORTHERN CALIFORNIA TONIGHT. IT WILL BE
QUITE CHILLY WITH NIGHTTIME TEMPERATURES IN THE TEENS AND 20S FOR AT
LEAST THE NEXT COUPLE OF NIGHTS. DAYTIME HIGHS MON WILL LIKELY REMAIN
BELOW FREEZING...EXCEPT ON THE COAST...WITH SOME SLIGHT WARMING TUE.
RW

.LONG TERM...DRY CONDITIONS EXPECTED THROUGH MUCH OF THE WEEK AS NW
FLOW ALOFT CONTINUES OVER THE NW STATES. EXPECT SOME OFFSHORE FLOW TO
CONTINUE BUT NO REINFORCING DISTURBANCES ARE SHOWN IN CURRENT MODELS
WHICH COULD TIGHTEN OFFSHORE PRESSURE GRADIENTS. PRECIP CHANCES WILL
INCREASE A LITTLE BY LATER IN THE WEEK...BUT THE MAIN THREAT FOR
RENEWED PRECIP WILL BEGIN SOMETIME NEXT WEEKEND. BEFORE THEN WEATHER
SYSTEM IN THE WESTERLIES WILL BE MAKING LANDFALL WELL TO
OUR S. RW

&&

.AVIATION...DRY OFFSHORE FLOW IS EXPECTED THROUGH THE NEXT 24 HOURS 
WITH VFR CONDITIONS.

KPDX AND APPROACHES...VFR CONDITIONS ARE EXPECTED THROUGH THE NEXT 
24 HOURS. BRISK EASTERLY WINDS WILL DEVELOP THIS MORNING AS OFFSHORE 
GRADIENTS INCREASE.  

&&

.MARINE...W SWELL AROUND 5 FT WILL CONTINUE TO DECREASE TO AROUND 3 
FT BY THIS EVENING. STRONG OFFSHORE FLOW WILL GENERATE EASTERLY WIND 
WAVES...BRINGING SEAS TO NEAR 10 FT IN THE OUTER MARINE ZONES BY 
THIS AFTERNOON. WEST SWELL AND EASTERLY WIND WAVES WILL RESULT IN 
CONFUSED SEAS...AT LEAST THROUGH EARLY NEXT WEEK. WINDS WILL  
INCREASE TO GALES BY THIS MORNING AS MODIFIED ARCTIC AIR MOVES 
ACROSS THE WATERS AND INCREASES THE OFFSHORE FLOW. EXPECT THE 
STRONGEST WINDS TO OCCUR WEST OF GAPS IN COASTAL TERRAIN. WINDS WILL 
EASE TO SMALL CRAFT ADVISORY LEVELS AGAIN BY MON MORNING.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...GALE WARNING FOR WINDS CAPE SHOALWATER TO FLORENCE THROUGH 
	  MONDAY MORNING.

&&

$$

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.