Area Forecast Discussion
Issued by NWS Portland, OR

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FXUS66 KPQR 101106
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
247 AM PST WED FEB 10 2016

.SYNOPSIS...MILD AIR MASS TO REMAIN OVER THE REGION THROUGH FRI.
WEAK FRONTS OFFSHORE WILL BRUSH THE NW TODAY AND THU...WITH VARIABLE
CLOUDINESS ACROSS THE REGION...ALONG WITH SOME SPOTTY LIGHT RAIN
ALONG THE COAST AND POSSIBLY INLAND. THAT CHANGES BY FRI...AS FIRST
IN A SERIES OF FRONTS PUSH INTO THE PAC NW. SHOWERY ON SATURDAY...BUT
MORE RAIN ARRIVES ON SUNDAY.
&&

.SHORT TERM...TODAY THROUGH FRIDAY...
UPPER RIDGE OVER THE PAC NW WILL SLOWLY SHIFT EASTWARD TODAY AND THU.
THAT MEANS MILD SOUTHWEST FLOW WILL TAKE HOLD OVER THE REGION. AT
SAME TIME...SEVERAL WEAKENING FRONTS WILL APPROACH FROM THE WEST.
WHILE MOST OF THE PRECIPITATION WILL REMAIN OFFSHORE...WILL SEE
CONSIDERABLY MORE IN WAY OF CLOUDS ACROSS THE REGION TODAY THROUGH
THU.

REMAINS OF THE FIRST FRONT SITS JUST OFFSHORE THIS AM...AND WILL MOVE
INLAND TODAY. NOT MUCH IN WAY OF RAIN...BUT SHOULD SEE SPOTTY LIGHT
RAIN ON THE COAST WITH ONLY LIGHT RAINFALL AMOUNTS. FURTHER
INLAND...SHOULD JUST SEE OCCASIONAL SPRINKLES OR POSSIBLY A BRIEF
LIGHT SHOWER. OVERALL...DRY INLAND TODAY AND TONIGHT.  MODELS
CONTINUE TO DEPICT THIS WEAK BOUNDARY LIFTING BACK TO THE N AS A WARM
FRONT ON THU. AGAIN...NOT A LOT OF PRECIPITATION BUT ENOUGH FOR
SPOTTY LIGHT RAIN...MAINLY ALONG THE COAST AND INTO SW WASHINGTON.

WITH LACK OF ANY AIR MASS CHANGE...AND WEAK WINDS OVER REGION... THE
MILD TEMPERATURE WILL CONTINUE. NORMALS HIGHS FOR THIS TIME OF FEB
ARE GENERALLY IN THE LOWER 50S. SO...WILL KEEP FORECAST HIGHS FOR
NEXT FEW DAYS IN THE MID TO UPPER 50S.

FOR PAST MANY DAYS...MODELS HAVE BEEN INDICATING FIRST DECENT SHOT OF
RAIN WOULD PUSH INTO THE REGION ON FRI AS A MODERATELY STRONG COLD
FRONT ARRIVES. NO CHANGES TO THAT THOUGHT TRAIN. WILL KEEP RAIN IN
FORECAST ON FRI...WITH 0.50 TO 1.00 INCH OVER COAST RANGE AND S WASH
CASCADES...WITH 0.25 TO 0.50 INCH ELSEWHERE.  SNOW LEVELS REMAIN
ABOVE 8000 FT THROUGH FRI AFTERNOON...THEN WILL LOWER TO 3500 TO 4000
FT BY LATE FRI NIGHT.      ROCKEY.


.LONG TERM...SATURDAY THROUGH TUESDAY...
COOLER ON SATURDAY...WITH SHOWERS OVER THE REGION. SNOW LEVELS
SITTING AROUND 3500 TO 4000 FEET ON SAT...WITH SOME NEW SNOW EXPECTED
OVER THE CASCADES. NOT A LOT...BUT COULD SEE 3 TO 8 INCHES OF NEW
SNOW AT THE PASSES AND ABOVE. RATHER PROGRESSIVE PATTERN OVER THE
PAC...WITH ANOTHER FRONT ARRIVING ON SUN. HAVE INCREASES PROB OF RAIN
ON SUNDAY. BRIEF BREAK ON MON...BUT LOOKS WET AFTERWARDS AS YET
ANOTHER FRONT ARRIVES ON TUE. REST OF NEXT WEEK LOOKS RATHER CLOUDY
AND WET...WITH SNOW LEVELS BOUNCING FROM 3500 TO 5500 FT.   ROCKEY.

&&

.AVIATION...VFR MOST AREAS ALTHOUGH THERE MAY BE SOME PATCHY
VALLEY FOG UNDER THE HIGH OVERCAST. AT THIS TIME...NOTHING IS AT
THE TAF TERMINALS AND KUAO IS THE ONLY SITE SHOWING ANY VISIBILITY
REDUCTION. KEUG BRIEFLY FOGGED IN EARLIER BUT INCREASING
SOUTHEASTERLY WINDS HAVE SCOURED IT OUT. OTHERWISE...EXPECT VFR
CONDS THROUGH 11/12Z. A WEAK FRONT BRUSHES THE COAST THIS
AFTERNOON AND MAY BRING HIGHER END MVFR CIGS TO THE COASTAL
TERMINALS. NOT MUCH IMPACT EXPECTED INLAND ASIDE FROM VERY LIGHT
RAIN POSSIBLE 16Z-03Z AS CONDS LIKELY REMAIN VFR.

KPDX AND APPROACHES...VFR NEXT 24 HRS. MAY GET SOME PERIODS OF
HIGHER TERRAIN OBSCURATION OVER THE CASCADES AS WEAK RAIN BANDS
CROSS THE AREA 20Z-03Z. /JBONK

&&

.MARINE...A DECAYING FRONT WILL CROSS THE WATERS TODAY ALTHOUGH
CONFIDENCE IS BELOW NORMAL WITH REGARD TO THE WIND STRENGTH. WIND
SPEEDS ARE CURRENTLY BEING OVERDONE BY MODELS BY A FEW KTS. ALSO
SHORTENED THE TIME OF THE SCA FOR WINDS BY SEVERAL HOURS BUT EVEN
WITH THE WEAKER WINDS, IT APPEARS THERE WILL STILL BE ENOUGH WIND
TO JUSTIFY THE SCA FOR A SEVERAL HOUR PERIOD OF FREQUENT 21-25 KT
GUSTS. SEAS WILL REMAIN BELOW CRITERIA DURING THE INITIAL EVENT
BUT BECOME SOMEWHAT STEEP REACHING 7-9 FT AT 11-13 SEC.

THE LARGE AND COMPLEX PARENT LOW CENTERED OVER THE GULF OF ALASKA
WELL OFFSHORE WILL SWING THE NEXT FRONT ACROSS THE WATERS
THURSDAY AND ANOTHER ON SATURDAY NIGHT/SUNDAY. THE THURSDAY SYSTEM
IS TRENDING WEAKER OVER THE LAST 24 HOURS BUT DOES STILL APPEAR TO
BE STRONGER THEN THE IMPENDING QUESTIONABLE FRONT. SUNDAY`S WOULD
BE THE STRONGEST ASSUMING MODELS SETTLE IN ON A COMMON SOLUTION.

REGARDLESS...THE SET OF EMBEDDED LOWS INSIDE THE PARENT LOW IS
GENERATING NUMEROUS SETS OF SWELL TRAINS. THE LEADING EDGE OF
SIGNIFICANT SEAS WILL REACH THE OUTER WATERS AROUND MIDNIGHT
TONIGHT. SEAS WILL POSSIBLY STAY 10-15 FEET AND BECOME CONFUSED AT
TIMES THROUGH AT LEAST SUNDAY. DECIDED TO ONLY ISSUE A SCA FOR
SEAS THROUGH FRIDAY DAYLIGHT WITH CONFIDENCE BECOMING LIMITED
THEREAFTER GIVEN THE TIME RANGE. /JBONK

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

WA...NONE.

PZ...SMALL CRAFT ADVISORY FOR WINDS FOR T0DAY ON ALL WATERS.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS ON ALL WATERS
 TODAY THROUGH FRI.

&&



$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND


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.


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