High Wind and Strong Wind in Oregon, October 10, 2015

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
951 AM PDT SAT OCT 10 2015

.SYNOPSIS...A RATHER STRONG MOIST COLD FRONT WILL SWEEP THROUGH
SOUTHWEST WASHINGTON AND NORTHWEST OREGON THIS AFTERNOON WITH A GOOD
DOSE OF RAIN AND SOME WIND...AND A SLIGHT CHANCE OF THUNDERSTORMS
FROM ABOUT SALEM NORTHWARD. POST FRONTAL SHOWERS IN THE EVENING WILL
DECREASE OVERNIGHT TONIGHT WITH DRYING SUNDAY UNDER A WEAK UPPER
RIDGE AFTER A FEW RESIDUAL CASCADE SHOWERS EARLY SUNDAY. THE NEXT
FRONT WILL WEAKEN AND DISSIPATE AS IT SAGS SOUTH INTO SOUTHWEST
WASHINGTON AND FAR NORTHWEST OREGON MONDAY INTO EARLY TUESDAY. THEN
AN UPPER RIDGE WILL BUILD IN RATHER STRONGLY FOR THE MIDDLE AND
LATTER PARTS OF NEXT WEEK FOR ANOTHER PERIOD OF DRY AND POTENTIALLY
MILD WEATHER. THE NEXT CHANCE OF RAIN LOOKS TO BE NEXT WEEKEND.
&&

.SHORT TERM...TODAY THROUGH MONDAY...THE FOCUS FOR TODAY WILL BE THE
STRONG MOIST PACIFIC COLD FRONT JUST OFF THE COAST THAT WILL SWEEP
THROUGH SOUTHWEST WASHINGTON AND NORTHWEST OREGON THIS AFTERNOON.
THIS FRONT HAS ALREADY SPREAD RAIN ONTO THE COAST AND INLAND TO CLOSE
TO KELSO THIS MORNING. THIS FRONT WILL BE ACCOMPANIED BY 115 KT UPPER
JET...AROUND 45 KT OF 850 MB INFLOW...AND PRECIPITABLE WATER VALUES
OF AROUND AN INCH AND A THIRD. ALL OF THIS ADDS UP TO A GOOD DOSE OF
RAIN AS THE FRONT MOVES THROUGH...WITH WINDY CONDITIONS AT THE COAST
AND BREEZY CONDITIONS INLAND. RAINFALL AMOUNTS LOOK TO BE 1 TO 1.5
INCHES AT THE COAST AND IN THE CASCADES...HIGHEST IN THE NORTH...WITH
0.25 TO 0.50 INCH INLAND. THE AMOUNTS WILL MAINLY BE LIMITED DUE TO
HOW QUICKLY THE FRONT MOVES THROUGH. THE FRONT AND WIND SHIFT WILL
MOVE ONSHORE ALONG THE COAST AROUND 20Z OR 21Z...AND BE EAST OF THE
CASCADES BY 00Z.

THERE HAS BEEN QUITE A BIT OF LIGHTNING ALONG THE FRONT OFFSHORE...
AND MODEL LIFTED INDEX AND INSTABILITY FORECASTS SUGGEST THAT THUNDER
IS A POSSIBILITY WITH AND BEHIND THE FRONT THIS AFTERNOON AND EARLY
EVENING FROM ABOUT SALEM NORTHWARD.

OVERALL THIS WILL BE A PRETTY DECENT FRONT...MORE POTENT THAN WHAT WE
SAW FRIDAY BUT NOT AS POTENT AS SOME OF OUR STRONGER WINTER TIME
SYSTEMS.

THE MODELS SAY THE SHOWERS WILL DECREASE OVERNIGHT TONIGHT AS A
SOMEWHAT FLAT UPPER LEVEL RIDGE MOVES INTO THE PACIFIC NORTHWEST...
WITH A FEW LINGERING NEAR THE CASCADES EARLY SUNDAY. THE MODELS ALSO
SHOW CLOUDS CONTINUING MOST OF THE AREA TONIGHT INTO SUNDAY MORNING
BEFORE BREAKING UP SUNDAY AFTERNOON WITH MORE SUNSHINE AND TEMPS
WARMING CLOSE TO 70 INLAND. THE UPPER RIDGE WILL CONTINUE SUNDAY
NIGHT AND MONDAY WITH MOSTLY DRY WEATHER. DECENT RADIATIONAL
CONDITIONS SUNDAY NIGHT WILL LEAD TO SOME COOL NIGHTTIME TEMPS....
WITH ANOTHER MILD DAY FOR THE MOST PART MONDAY. THE NEXT WEAKENING
EAST WEST ORIENTED FRONT WILL LIKELY SAG SOUTH ONTO THE SOUTH
WASHINGTON COAST MONDAY AFTERNOON FOR A LITTLE RAIN. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...A SLIGHT CHANCE OF RAIN WILL CONTINUE
MONDAY NIGHT FOR THE NORTHERNMOST AREAS OF THE LOCAL FORECAST AREA AS
A WEAK FRONT BRUSHES BY. UPPER LEVEL RIDGING WILL BEGIN TO BUILD IN
ON TUESDAY AND WILL REMAIN IN PLACE THROUGH MUCH OF THE UPCOMING WEEK
FOR WARM AND DRY WEATHER. BY THURSDAY...TEMPERATURES MAY WARM TO 10
TO 15 DEGREES ABOVE NORMAL...INTO THE UPPER 70S. IF MODELS CONTINUE
TO TREND WARMER AS THEY HAVE BEEN...COULD SEE SOME 80S AGAIN INLAND.
BOWEN
&&

.AVIATION...MOIST SOUTHWESTERLY FLOW CONTINUING THIS MORNING WITH AN
APPROACHING STRONG COLD FRONT BRINGING INCREASING WINDS AND RAIN
ALONG THE COAST. MAINLY VFR CONDITIONS PREVAIL ACROSS THE INTERIOR.
EXPECT MVFR CIGS TO PUSH INLAND THIS AFTERNOON AS THE FRONT MOVES
ONSHORE. AT THE COAST...LOW MVFR TO IFR CONDITIONS WILL CONTINUE
THROUGH THE DAY. GUSTY S-SW WINDS UP TO 45 KT WILL DEVELOP ALONG THE
COAST LATER THIS MORNING WITH GUSTS TO 30 KT DEVELOPING INLAND DURING
THE AFTERNOON. EXPECT A BRIEF PERIOD OF HEAVIER RAIN AND
DETERIORATING VSBYS WITH THE FRONTAL PASSAGE. THE FRONT TO PUSH
ONSHORE AROUND BETWEEN 18Z AND 20Z AND INTO THE INTERIOR BETWEEN 21Z
AND 00Z SUN. THERE SHOULD BE AN IMPROVEMENT IN CONDITIONS BEHIND THE
FRONT...BUT WITH PLENTY OF LOW LEVEL MOISTURE REMAINING...EXPECT VFR
CIGS TO REDEVELOP ALONG THE COAST THIS EVENING AND OVERNIGHT FOR THE
INTERIOR.

KPDX AND APPROACHES...VFR PREVAILING THIS MORNING. EXPECT MVFR CIGS
TO ARRIVE THIS AFTERNOON AS THE COLD FRONT MOVES ONSHORE. RAIN BEGINS
TO INCREASE AFTER 20Z ALONG WITH POSSIBLE GUSTY S WINDS TO 25 KT
THROUGH 00Z AS FRONT MOVES THROUGH. PYLE
&&

.MARINE...GUSTY ADVISORY STRENGTH WINDS AND 12-14 FT SEAS OVER THE
WATERS THIS MORNING. A STRONG COLD FRONT WILL MOVE RAPIDLY THROUGH
THE WATERS DURING THE MORNING HOURS AND THEN PUSH ONSHORE THIS
AFTERNOON. EXPECT A SHARP INCREASE IN WINDS UPON ARRIVAL...WITH
SOUTHERLY GALES OVER THE WATERS LATER THIS MORNING GUSTING 35 TO 40
KT...WITH A FEW GUSTS TO 45 KT POSSIBLE CLOSE TO SHORE WITH SOME
COASTAL JET ENHANCEMENT POSSIBLE. EXPECT WAVE HEIGHTS TO INCREASE
FURTHER ALONG AND BEHIND THE FRONT...REACHING AROUND 15 TO 17 FT BY
THIS AFTERNOON. EXPECT RATHER CONFUSED SEAS WITH COMBINATION OF
DECREASING S SWELL AND BUILDING W SWELL...ALONG WITH FRESH SWELL/WIND
WAVES.

SEAS AND WINDS EASE LATER THIS AFTERNOON AND TONIGHT...AND SWELL WILL
BECOME DOMINATED BY W COMPONENT SUNDAY. ANOTHER WEAK FRONT WILL CLIP
THE WATERS MONDAY AND BRING A SLIGHT BUMP IN SEAS AND POSSIBLE SMALL
CRAFT WINDS. SEAS LIKELY REMAIN NEAR OR ABOVE 10 FT UNTIL TUESDAY.
OVERALL PATTERN QUIETER BY MIDWEEK WITH BUILDING HIGH PRESSURE. PYLE
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WARNING UNTIL 5 PM PDT THIS AFTERNOON FOR COASTAL WATERS
     FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     MIDNIGHT PDT TONIGHT.

&&

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.