High Wind in Washington, February 5 to 6, 2015

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
841 PM PST THU FEB  5 2015

.SYNOPSIS...A STRONG JET EXTENDING ACROSS THE NORTH PACIFIC WILL
CONTINUE TO SEND WAVES OF STORM SYSTEMS TOWARD THE PACIFIC NORTHWEST
THROUGH EARLY NEXT WEEK. THE NEXT FRONTAL WAVE WILL MOVE TO THE COAST
AND PRODUCE ANOTHER SURGE OF RAIN AND COASTAL WIND TONIGHT AND FRIDAY
MORNING. MORE FRONTS ARRIVE SATURDAY AND MONDAY. THE TWO STRONGEST
LOWS OF THIS SERIES ARE EXPECTED SATURDAY AND AGAIN MONDAY WITH MORE
RAIN AND WIND...WITH SOME OF THE SOUTH WIND POSSIBLY EXTENDING INTO
THE VALLEYS. LOOK FOR SOME DRYING AND CALMER WEATHER STARTING THE
MIDDLE OF NEXT WEEK.

&&

.UPDATE...LIGHT TO MODERATE RAIN HAS SPREAD OVER NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. EVEN THE SOUTH WILLAMETTE VALLEY...WHICH SAW
LITTLE RAIN EARLIER TODAY...IS SEEING RAIN RATES OF A FEW HUNDREDTHS
PER HOUR. RAIN WILL CONTINUE OVERNIGHT BUT WIND ALONG THE COAST WILL
BE THE BIGGER STORY TONIGHT WITH THE APPROACH OF THE NEXT COLD FRONT.
THE 00Z NAM AND GFS SHOW BOUNDARY LAYER WINDS OF AROUND 50 KTS FOR
THE CENTRAL OREGON COAST WITH SLIGHTLY LIGHTER WINDS FARTHER NORTH.
HOWEVER...850 MB WINDS IN BOTH MODELS ARE AROUND 80 KTS FOR THE
CENTRAL OREGON COAST AND STILL 60-70 KT ALONG THE NORTH OREGON AND SW
WASHINGTON COASTS...SO STILL THINK HIGH WINDS ARE LIKELY FOR THE
BEACHES AND HEADLANDS AND WILL RIDE THE HIGH WIND WARNING AS IS. WITH
THAT BEING SAID...HIGHEST WINDS WILL LIKELY BE ALONG THE CENTRAL
OREGON COAST. OVERALL THE NEAR-TERM FORECAST APPEARS TO BE ON TRACK
WITH NO CHANGES NECESSARY THIS EVENING. WITH CLOUDS AND RAIN...IT
WILL BE A WARM NIGHT WITH LOWS AROUND 50 IN THE VALLEY AND COASTAL
TEMPERATURES NOT DROPPING MUCH BELOW THE MID 50S. THERE'S A PRETTY
GOOD CHANCE WE'LL SEE SOME RECORD WARM LOWS AGAIN FRIDAY.

SKIPPING AHEAD A BIT IN THE FORECAST...SATURDAY'S SYSTEM PROVIDES THE
NEXT BIG FORECAST QUESTION WITH REGARDS TO WINDS. THE 00Z NAM AND GFS
ARE IN SLIGHTLY BETTER AGREEMENT AS FAR AS THE POTENTIAL FOR WINDS
AWAY FROM THE COAST...BUT THE NAM STILL SHOWS A STRONGER LOW JUST
OFFSHORE VS THE GFS'S OPEN WAVE FARTHER OFFSHORE. AS SUCH...THE NAM
INDICATES STRONGER WINDS SATURDAY WITH 850 MB WINDS OVER THE SOUTH
VALLEY OF UP TO 70 KT AND CLOSER TO 60 KT ELSEWHERE IN THE VALLEY.
THE GFS PEAKS AT ABOUT 60 KT ACROSS THE VALLEY. BUFKIT ANALYSIS SHOWS
SOME POTENTIAL FOR THESE WINDS TO REACH THESE SURFACE...ALBEIT A
BRIEF POTENTIAL CENTERED AROUND NOON SATURDAY AND FAVORING THE SOUTH
VALLEY. THERE IS PLENTY OF DISAGREEMENT AMONG MODELS AND THEREFORE
UNCERTAINTY IS HIGH ABOUT THESE WINDS SO WILL CERTAINLY NOT ISSUE ANY
WIND PRODUCTS FOR THE VALLEY AT THIS POINT...BUT IT'S SOMETHING TO
KEEP A CLOSE EYE ON OVER THE NEXT 24 HOURS. BOWEN

.SHORT TERM (PREVIOUS DISCUSSION)...SATELLITE AND MODELS SHOW TRAIN
OF LOW PRESSURE SYSTEMS STRETCHING ACROSS THE NORTH PACIFIC. THERE IS
A STRONG ZONAL JET STRETCHING BETWEEN 30N AND 40N BEFORE TURNING
TOWARD THE U.S. WEST COAST. THE JET WILL INTERACT WITH THE LOW AN
PRODUCE SMALL FAST MOVING LOWS OR WAVES THAT WILL RIDE ALONG A
FRONTAL BOUNDARY TOWARD THE PACNW. THE NEXT WAVE WILL ARRIVE TONIGHT
WITH ENOUGH PUNCH TO BRING ANOTHER ROUND OF HIGH WINDS TO THE COAST.
THIS SHOULD BE SIMILAR TO THIS MORNINGS SYSTEM WITH HIGH WINDS
AFFECTING THE BEACHES AND HEADLAND AREAS LATER TONIGHT AND EARLY
FRIDAY. A WEAKER FRONTAL WAVE FOLLOWS DURING THE DAY FRIDAY TO
MAINTAIN BREEZY CONDITIONS.

ANOTHER FRONTAL WAVE ARRIVES SAT. MODELS HAVE BEEN ADVERTISING
POSSIBLE HIGH WINDS ON THE COAST WITH THIS SYSTEM WITH SOME
VARIATIONS. THE NAM IN PARTICULAR HAS BEEN YO-YOING ON THE STRENGTH
OF THIS SYSTEM. 12Z NAM HAD A CLOSED LOW MOVING INTO SW WASHINGTON
AS IT WEAKENED. THE 18Z RUN IS MUCH WEAKER AND MORE IN-LINE WITH THE
GFS AND ECMWF. THE LATEST 18Z NAM HAS GENERATED ANOTHER LOW THAT
RAPIDLY SPINS UP AND CROSSES THE WATERS SAT NIGHT AS IT HEADS TOWARD
THE SOUTH WA COAST. THE FINAL CLOSING SYSTEM IS CURRENTLY FORECAST
TO APPROACH LATE SUNDAY BRINGING THE POSSIBILITY OF HIGH WINDS ON
THE COAST AND PARTS OF THE INTERIOR LATE SUN NIGHT. WITH SUCH A
STRONG JET MODEL SOLUTIONS WILL LIKELY CONTINUE TO VARY AS THEY
ATTEMPT TO RESOLVE THE PROGRESSIVE PATTERN ACROSS THE PACIFIC.

WE SHOULD SEE QUITE A BIT OF RAINFALL FROM THESE SYSTEMS DUE TO THE
TAP OF SUBTROPICAL MOISTURE ASSOCIATED WITH THIS FRONTAL BOUNDARY.
PRECIPITABLE WATER VALUES FEEDING THIS FRONT ARE UP AROUND 1.3 INCHES
OR SO...AND WILL BE TRANSPORTED INTO OUR AREA WITH SURGES OF 850 MB
WINDS EXCEEDING 60 KT AT TIMES. FORTUNATELY...THE RAIN WILL COME IN
WAVES WITH ENOUGH OF A BREAK IN BETWEEN SYSTEMS TO LIMIT FLOODING
POTENTIAL. THE MAIN MORE PERSISTENT FOCUS OF THE HEAVIER RAIN WILL BE
TO THE SOUTH OF THE FORECAST AREA IN SOUTHWEST OREGON AND NORTHERN
CALIFORNIA. HOWEVER...THROUGH NEXT MONDAY...RAINFALL AMOUNTS WILL
PROBABLY REACH 2 TO 3 INCHES FOR THE INTERIOR VALLEYS...AND 4 TO 7
INCHES FOR THE COAST...COAST RANGE AND CASCADES.

SNOW LEVELS WILL REMAIN HIGH...GENERALLY ABOVE 7000 OR 8000 FEET
THROUGH FRIDAY THEN LOWER TO ABOUT 5000 TO 6000 FEET SATURDAY. NOT
MUCH HELP FOR THE SNOW PACK IS EXPECTED. /26

.LONG TERM...THE TROUGH OF LOW PRES EXPECTED OFF THE COAST THIS
WEEKEND CONTINUES TO BE FORECAST BY MODELS TO SHIFT INLAND MON
BEFORE BECOMING ABSORBED INTO THE LONGWAVE TROUGH OVER THE CENTRAL
AND EASTERN STATES. IN ITS PLACE ANOTHER NARROW RIDGE IS EXPECTED
FOR MIDWEEK. WILL KEEP POPS HIGH FOR THE SUN NIGHT THROUGH MON
EVENING TIME PERIOD AS THE STRONG SYSTEM MOVES THROUGH WITH DEEP
MOISTURE. BY TUE ONSHORE FLOW BEGINS TO WEAKEN CONSIDERABLY AS THE
RIDGE BUILDS OFFSHORE...SO WILL SEE CHANCES FOR SHOWERS DECREASING
BY EVENING. WED MODELS IN GOOD AGREEMENT WITH THE RIDGE PUSHING IN
FOR DRY WEATHER. THU HOWEVER SOME DISCREPANCIES BEGIN TO
APPEAR...WITH GFS HANGING ON TO THE RIDGE BUT ECWMF PUSHING A WEAK
FRONT ONTO THE COAST. THE RIDGE HOWEVER REMAINS FAIRLY STRONG OVER
THE INTERIOR WITH THE ECMWF...SO WILL LIMIT POPS THU TO JUST A
SLIGHT CHANCE FOR COASTAL AREAS.
&&

.AVIATION...A MOIST FRONTAL BOUNDARY WILL BRING PERIODIC MODERATE
TO HEAVY RAIN TO THE REGION THROUGH FRI. EXPECT LITTLE CHANGE IN
THE FLIGHT CATEGORIES THROUGH TONIGHT WITH PREDOMINANTLY MVFR
CONDITIONS SHOULD PERSIST AT THE COAST...AND MAINLY VFR CONDITIONS
INLAND. HOWEVER...PERIODS OF MVFR ACROSS THE INTERIOR DURING
PERIODS OF HEAVIER RAIN ARE PROBABLE. A WAVE RIDING ALONG THE
FRONTAL BOUNDARY WILL BRING ANOTHER ROUND OF INCREASING RAIN AND
SOUTHERLY WINDS TONIGHT AND EARLY FRI MORNING...ESPECIALLY ALONG
THE COAST. KAST AND KONP WILL LIKELY SEE GUSTS OF 35 TO 40 KT AT
TIMES BETWEEN 08Z AND 17Z FRI. RAIN INTENSITY INCREASES ACROSS
THE INTERIOR AFT 18Z FRI WITH INCREASINGLY LIKELY PERIODS OF MVFR
TO IFR VSBYS.

KPDX AND APPROACHES...MAINLY VFR CONDITIONS SHOULD PERSIST
THROUGH FRI MORNING WITH CONTINUING RAIN. BREEZY E-SE SURFACE
WINDS CONTINUE TO REACH THE TERMINAL...WITH STRONG S LOW-LEVEL
WINDS...WHICH WILL CONTINUE THE POTENTIAL FOR LLWS. RAIN
INTENSITY INCREASED AFT 18Z FRI THROUGH FRI EVENING...WHICH LIKELY
REDUCES VSBYS TO MVFR OR PERHAPS IFR AT TIMES.	 CULLEN

&&

.MARINE...THE VERY ACTIVE WEATHER PATTERN CONTINUES. LOW END
SOUTHERLY GALE GUSTS CONTINUE OVER THE WATERS THIS EVENING AND
WILL AGAIN INCREASE LATER TONIGHT THROUGH EARLY FRIDAY AS ANOTHER
LOW PRESSURE SYSTEM MOVES ALONG A STALLED FRONTAL BOUNDARY
SITTING JUST OFFSHORE. EXPECT CONDITIONS LARGELY SIMILAR TO THE
SYSTEM THAT MOVED THROUGH LAST NIGHT AND EARLY THIS MORNING.
NAMELY...MODERATE TO HIGH END GALE FORCE WINDS OVER THE WATERS
WITH A FEW LOCAL STORM FORCE GUSTS TO 50 KT...PRIMARILY OVER THE
CENTRAL OREGON WATERS.

THERE MAY BE A RELATIVE LULL IN THE WINDS FRI AFTERNOON AND FRI
NIGHT...WITH GUSTS EASING BACK TO AROUND 30 TO 35 KT. WILL
MAINTAIN THE GALE WARNING THROUGH 6 PM FRIDAY FOR NOW...BUT WOULD
NOT BE SURPRISED IF WINDS EASE ENOUGH TO END IT A FEW HOURS
EARLIER....PARTICULARLY FOR THE NORTHERN ZONES. HOWEVER...THE
ACTIVE PATTERN CONTINUES WITH ADDITIONAL STRONG SYSTEMS ON TAP FOR
SATURDAY AND SATURDAY NIGHT. HOWEVER...SOME UNCERTAINTY AS TO HOW
STRONG THESE WILL BE. FOR NOW...WILL INDICATE 40 KT GUSTS THROUGH
THIS PERIOD...BUT CANNOT RULE OUT STRONGER GALES OR EVEN STORM
FORCE WINDS AT SOME POINT SATURDAY. YET ANOTHER SYSTEM IS EXPECTED
LATE SUNDAY NIGHT AND MONDAY...WITH ANOTHER ROUND OF HIGHER END
GALES TO PERHAPS STORM FORCE WINDS POSSIBLE

SEAS ARE EXPECTED TO CONTINUE IN THE 17 TO 19 FT RANGE FOR THE
NEXT SEVERAL DAYS...LIKELY BUILDING TO 20 TO 22 FT AT TIMES DURING
THE PERIODS OF STRONGEST WINDS. WAVE PERIOD WILL REMAIN RELATIVELY
LOW AT AROUND 12 SECONDS...SO NOT ANTICIPATING ANY ISSUES WITH
RESPECT TO HIGH SURF CONDITIONS ALONG THE COAST.

THE PROLONGED PERIOD OF ACTIVE WEATHER LOOKS TO FINALLY COME TO AN
END FINALLY BEGIN TO WIND DOWN ON TUESDAY AND WEDNESDAY WITH WEAK
HIGH PRESSURE BUILDING IN OVER THE WATERS. CULLEN

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 7 AM PST FRIDAY FOR CENTRAL OREGON
     COAST-NORTH OREGON COAST.

WA...HIGH WIND WARNING UNTIL 7 AM PST FRIDAY FOR SOUTH WASHINGTON
     COAST.

PZ...GALE WARNING UNTIL 6 PM PST FRIDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL MIDNIGHT
     PST FRIDAY NIGHT.

&&

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.