431 
FXUS66 KPQR 210410
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
809 PM PST FRI NOV 20 2009

.SYNOPSIS...RESIDUAL SHOWERS WILL CONTINUE THE REMAINDER OF THE NIGHT
AFTER THE PASSAGE OF A COLD FRONT. ANOTHER FRONT APPROACHES  LATER
SATURDAY...WITH STRONG WINDS POSSIBLE ON THE COAST AND
SIGNIFICANT SNOW EXPECTED IN THE CASCADES. THE NEXT STORM ARRIVES
LATER MONDAY.  
&&

.SHORT TERM...STILL CONSIDERABLE SHOWERS THIS EVENING...ESPECIALLY
ALONG THE CASCADES AND WILL KEEP THE ADVISORY FOR SNOW. A WARM FRONT
APPROACHES SATURDAY WITH INCREASING WINDS ALONG THE COAST CONSISTENT
WITH HIGH WIND WATCH.

THE TRAILING COLD FRONT GETS SLOWED BY A WAVE WITH ANOTHER LOW
DEVELOPING. THE LOWS PUSHES TO THE COAST SATURDAY NIGHT. ALL THE
MODELS HAVE VARIED SOLUTIONS...MANY OF WHICH WOULD RESULT IN
SIGNIFICANT WINDS IN THE INTERIOR AT FIRST LOOK. BUT...THE UPPER
TROUGH BECOMES NEGATIVELY TILTED...SOMEWHAT MORE IN THE NAM THAN THE
GFS...WITH MOMENTUM TRANSFERRING SOUTH. NOT GOOD FOR A STRONG
SOUTHERLY PUSH OF WINDS. ALSO THE SURFACE LOW IS FILLING AS IT MOVES
INLAND AND THE LOW IS NOT MOVING NORTH OR NORTH NORTHEASTWARD
ALLOWING THE STRONG UP VALLEY PUSH OF WINDS.

SO WILL WAIT TO SEE IF WE GET A BETTER AND MORE CONSISTENT LOOK ON
LATER RUNS ON DEALING WITH THE WINDS. WITH THAT SECOND WAVE SLOWING
THINGS DOWN...WILL EXPAND THE WINTER STORM WATCH TO COVER ALL DAY
SUNDAY IN THE CASCADES RATHER THAN JUST THE MORNING. SS 

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEAK HIGH PRES
BUILDS OVER THE FORECAST AREA MON NIGHT. 
MODELS SHOW A WEAK SYSTEM APPROACH THE COAST EARLY TUE...BUT IT 
TRACKS FURTHER NORTH AND LIGHTLY BRUSHES THE FAR NORTHWEST CORNER OF 
THE CWA. THIS RIDGE IS MORE PERSISTENT THAN PREVIOUS MODEL RUNS 
SUGGESTED. IT MANAGES TO DELAY THE ARRIVAL OF A SECOND SYSTEM 
THROUGH THUR. BY MID NEXT WEEK...MODELS DISAGREE ON THE SOLUTION FOR 
THE WEEKEND. GFS MODEL RUNS ARE INCONSISTENT...THE 06Z RUN HELD BACK 
ON PRECIP THROUGH THURS NIGHT BUT THE CURRENT RUN SHOWS RAIN 
EXTENDING TO THE CASCADES THURS NIGHT. SO FAR...MODELS SUGGEST A 
FAIRLY NICE WEEKEND AS ANOTHER UPPER HIGH PRES TEMPORARILY SETS UP 
OVER THE PAC NW. LRAMIREZ

&&

.AVIATION...COOL SHOWERS CONTINUE TO STREAM IN OFF THE PACIFIC THIS 
EVENING IN UNSTABLE WESTERLY FLOW. VFR CONDITIONS ARE EXPECTED 
ACROSS ALL AREAS TONIGHT WITH A 40% CHANCE OF MVFR CONDITIONS IN AND 
NEAR SHOWERS. A WARM FRONT WILL BRING RAIN AND MVFR CONDITIONS TO 
THE COAST AND COAST RANGE BY MIDDAY SATURDAY.

KPDX AND APPROACHES...CONDITIONS ARE EXPECTED TO REMAIN PRIMARILY  
VFR TONIGHT WITH A 40% CHANCE OF MVFR CONDITIONS IN AND NEAR 
SHOWERS. VFR CONDITIONS ARE EXPECTED SATURDAY.

&&

.MARINE...SMALL CRAFT WINDS WILL CONTINUE THROUGH SATURDAY MORNING 
BEFORE THE NEXT STRONGER FRONT BOOSTS GUSTS TO LOW END GALE CRITERIA 
SATURDAY AFTERNOON WITH THE POSSIBILITY OF ANOTHER WAVE GENERATING 
STRONG GALES AND POSSIBLY STORM FORCE WINDS BY LATE SATURDAY NIGHT 
INTO SUNDAY MORNING. SEAS CURRENTLY HOVERING AROUND 12 FT AND SHOULD 
BUILD TO 16 TO 18 BY SATURDAY NIGHT.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR     
   THROUGH SAT EVENING.
SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO     
   FLORENCE THROUGH SAT MORNING. 
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER TO   
   FLORENCE THROUGH SAT MORNING.
GALE WARNING CAPE SHOALWATER TO CASCADE HEAD SAT MORNING     
   THROUGH LATE SATURDAY NIGHT.        
GALE WARNING CASCADE HEAD TO FLORENCE SAT MORNING THROUGH    
   SATURDAY EVENING.     
STORM WATCH CASCADE HEAD TO FLORENCE SAT EVENING THROUGH     
   SUNDAY MORNING. 
SNOW ADVISORY FOR THE SOUTH WASHINGTON AND NORTH OREGON      
  CASCADES THROUGH SAT MORNING.
WINTER WEATHER WATCH FOR SNOW FOR THE SOUTH WASHINGTON AND
  NORTH OREGON CASCADES AND THE CASCADES IN LANE COUNTY FOR
  SATURDAY AFTERNOON THROUGH SUNDAY.
HIGH WIND WATCH FOR THE NORTHERN AND CENTRAL OREGON COAST    
 FOR SAT AFTERNOON AND NIGHT.      
&&

$$

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.