Area Forecast Discussion
Issued by NWS Portland, OR

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FXUS66 KPQR 052139
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
230 PM PDT SUN JUL  5 2015

.SYNOPSIS...HOT WEATHER WILL CONTINUE OVER MOST OF THE REGION THROUGH
MIDWEEK AS A STRONG RIDGE OF HIGH PRESSURE ALOFT REMAINS OVER THE
AREA. THE EXCEPTION IS THE COASTAL REGION...WHERE COOLER MARINE AIR
WILL HUG THE COASTLINE THE NEXT SEVERAL DAYS.  AN UPPER LOW OFF
CALIFORNIA MAY DRIFT FAR ENOUGH NORTH TUE/WED TO BRING THUNDERSTORMS
UP THE CASCADE CREST TO LANE COUNTY BY MIDWEEK. RELIEF FROM THE HEAT
MAY COME LATER THIS WEEK AS THE UPPER RIDGE BREAKS DOWN ENOUGH TO
ALLOW STRONGER ONSHORE FLOW.

&&

.SHORT TERM...TEMPERATURES AT 2PM THIS AFTERNOON ARE RUNNING 2 TO 5
DEGREES ABOVE SATURDAY AFTERNOON READINGS...SO WE REMAIN ON TRACK TO
REACH MID 90S AT MANY INLAND LOCATIONS TODAY.  SOME RECORD HIGHS
WILL LIKELY BE SET TODAY IN NORTHWEST OREGON WITH EXISTING DAILY
RECORDS OF 94...93 AND 95 AT PORTLAND...VANCOUVER AND TROUTDALE...
RESPECTIVELY.

THE STRONG UPPER LEVEL RIDGE OF HIGH PRESSURE REMAINS ENTRENCHED
OVER NE PACIFIC AND STRETCHES SOUTHWARD TO THE FOUR CORNERS REGION.
NOT MUCH CHANGE EXPECTED THE NEXT FEW DAYS...SO THE PROLONGED PERIOD
OF HOT WEATHER WILL CONTINUE OVER MOST OF THE INLAND AREA THROUGH
WEDNESDAY WITH HIGH TEMPERATURES IN THE 90S. THE COAST WILL REMAIN
PLEASANT WITH TEMPERATURES IN THE 60S AND 70S AS COOLER MARINE AIR
HUGS THE COASTLINE. EXPECT TO SEE A SOUTHERLY SURGE OF MARINE AIR
PUSH NORTHWARD ALONG THE COAST TONIGHT. DEPENDING ON HOW DEEP THIS
PUSH OF MARINE AIR CAN GET...IT MAY SQUEEZE A LITTLE MARINE AIR INTO
THE COASTAL RANGE GAPS AND PROVIDE A LITTLE TEMPERATURE RELIEF TO
COMMUNITIES ON THE WEST SIDE OF THE COAST RANGE.

ANOTHER FEATURE OF INTEREST IS AN UPPER LEVEL LOW PRESSURE THATS BEEN
NEARLY STATIONARY OFF THE CALIFORNIA COAST THE PAST COUPLE DAYS. AS
THIS SYSTEM EVENTUALLY MOVES EASTWARD BY MID WEEK...IT MAY BRING
SOME MOISTURE NORTHWARD INTO THE LANE COUNTY CASCADES ON TUES/WED.
THE MOISTURE AND ENERGY FROM THE UPPER LEVEL LOW MAY BRING A SLIGHT
CHANCE OF THUNDERSTORMS TO THE LANE COUNTY CASCADES TUES AND WED. TW

.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...CONFIDENCE CONTINUES
TO INCREASE THAT REX BLOCK PATTERN WITH PERSISTENT HIGH PRESSURE
OVER THE PACIFIC NORTHWEST WILL BREAK DOWN BY FRIDAY COOLING
TEMPERATURES LATE THIS WEEK. AS THE RIDGE BREAKS DOWN...EXPECT
TEMPERATURES TO BE SOMEWHAT COOLER ON THURSDAY WITH HIGHS AROUND 5
DEGREES COOLER THAN WEDNESDAY INLAND. COOLER MARINE AIR MOVES IN
THURSDAY NIGHT WITH MORNING CLOUDS ON FRIDAY...WHICH WILL COOL HIGH
TEMPERATURES ANOTHER 5 DEGREES FOR FRIDAY AFTERNOON. AS UPPER-LEVEL
TROUGH MOVES THROUGH THURSDAY AND FRIDAY...THERE WILL BE A CHANCE
FOR A FEW SHOWERS OR THUNDERSTORMS IN THE LANE COUNTY CASCADES.
PATTERN OF MORNING CLOUDS WITH MARINE AIR OVER THE REGION WILL KEEP
TEMPERATURES CLOSER TO NORMAL SATURDAY AND SUNDAY. -MCCOY
&&

.AVIATION...HIGH PRES ALOFT PERSISTS THROUGH MON. IFR MARINE
STRATUS LOOKS LIKELY TO PERSIST ALONG MOST OF THE CENTRAL OREGON
COAST TODAY. SOUTHERLY WINDS SHOULD PUSH THE STRATUS BACK NORTH
ALONG THE N OREGON AND S WASHINGTON COAST LATER THIS AFTERNOON AND
THIS EVENING...WHERE IT WILL REMAIN INTO MON AM. VFR TO PERSIST
THROUGH MON FOR THE INLAND TAF SITES...BUT EXPECT SOME SCATTERED
TO BROKEN MID AND HIGH CLOUDS TO MOVE IN FROM THE SOUTH STARTING
MON AM. THERE IS A SLIGHT CHANCE THAT SOME MARINE STRATUS MAY BE
ABLE TO PUSH INTO THE VICINITY OF THE KEUG TERMINAL.

KPDX AND APPROACHES...VFR WILL CONTINUE THROUGH MONDAY. PYLE

&&

.MARINE...A THERMALLY INDUCED SURFACE TROUGH HAS MOVED OFFSHORE
TODAY. THIS HAS SIGNIFICANTLY WEAKENED THE PRES GRADIENT OVER THE
COASTAL WATERS AND OBSERVED WINDS ARE 15 KT OR LESS TODAY. THE
WEAK GRADIENT WILL CONTINUE THROUGH AT LEAST WED...WITH WINDS
MOSTLY REMAINING BELOW 15 KT. THE SURFACE TROUGH WILL DISSIPATE
TUE NIGHT AND WED...BRINGING A RETURN TO THE SEASONAL
NORTHWESTERLY WIND PATTERN AS HIGH PRES OVER THE NE PAC BEGINS TO
BUILD BACK OVER THE WATERS.

SEAS CURRENTLY SIT AT 7 TO 8 FT WITH A PERIOD OF 9 TO 10 SECONDS.
EXPECT THEM TO GRADUALLY SUBSIDE LATER TODAY AND TONIGHT. SEAS
SHOULD REMAIN 5 FT OR LOWER FOR MUCH OF NEXT WEEK. PYLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
  OR...HEAT ADVISORY UNTIL MIDNIGHT PDT WEDNESDAY NIGHT FOR CENTRAL
  COLUMBIA RIVER GORGE-SOUTH WILLAMETTE VALLEY-CENTRAL WILLAMETTE
  VALLEY-GREATER PORTLAND METRO AREA-LOWER COLUMBIA-NORTHERN OREGON
  CASCADE FOOTHILLS-UPPER HOOD RIVER VALLEY-WESTERN COLUMBIA RIVER
  GORGE.


WA...HEAT ADVISORY UNTIL MIDNIGHT PDT WEDNESDAY NIGHT FOR CENTRAL
     COLUMBIA RIVER GORGE-GREATER VANCOUVER AREA-I-5 CORRIDOR IN
     COWLITZ COUNTY-SOUTH WASHINGTON CASCADE FOOTHILLS-WESTERN
     COLUMBIA RIVER GORGE.

PZ...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 6 AM TO
10 AM PDT MONDAY.

&&

$$

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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