Area Forecast Discussion
Issued by NWS Portland, OR

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FXUS66 KPQR 311613
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
910 AM PDT FRI JUL 31 2015

.SYNOPSIS...STRONG UPPER LEVEL HIGH PRESSURE WILL KEEP VERY HOT
WEATHER IN PLACE TODAY. UPPER LEVEL HIGH PRESSURE WILL MOVE EAST OF
THE REGION AND ALLOW TEMPERATURES TO GRADUALLY COOL THROUGH THE
MIDDLE OF NEXT WEEK. MONSOONAL MOISTURE FROM THE SOUTH WILL BRING A
SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM TO THE OREGON CASCADE
CREST LATE IN THE WEEKEND AND EARLY NEXT WEEK...BUT CONFIDENCE
REMAINS LOW.

&&

.SHORT TERM...TODAY THROUGH MONDAY...ANOTHER HOT DAY EXPECTED ACROSS
THE REGION. THE EXCEPTION IS THE COAST WHERE LIGHT ONSHORE FLOW IS
BRINGING COOLER MARINE AIR TO THE COASTAL STRIP. INLAND TEMPS WILL
ONCE AGAIN REACH INTO THE CENTURY MARK...BUT EXPECTED TO TOP A
COUPLE OF DEGREES BELOW YESTERDAY/S READINGS. MOSTLY NOTABLE COOLING
WILL BE IN THE LOWER COLUMBIA NEAR KELSO. LEAST AMOUNT OF COOLING
WILL BE IN THE SOUTH AND CENTRAL VALLEY WHERE TEMPS WILL ONCE AGAIN
BE OVER 100 DEGREES.

SATELLITE IMAGERY THIS MORNING SHOWS SOME LOW CLOUDS ALONG THE NORTH
COAST. THERE IS ALSO A LITTLE  SMOKE IN THE FAR SOUTHERN THAT IS
MOVING NORTHWARD FROM THE FIRE IN SW OREGON. ELSEWHERE...MOSTLY
SUNNY ACROSS THE REGION.

THE UPPER LEVEL RIDGE AXIS WILL SHIFT EAST OF THE REGION OVER THE
WEEKEND RESULTING IN MID LEVEL SOUTHERLY FLOW WHICH WILL BRING AN
INCREASE IN MID TO UPPER LEVEL CLOUDS. MODEL SOUNDINGS SHOW SOME OF
THE INITIAL MOISTURE WILL LIKELY BE TOO HIGH TO PRODUCE ELEVATED
THUNDERSTORMS ON SATURDAY...BUT THIS MAY BEGIN TO CHANGE TOWARDS
SATURDAY NIGHT OR SUNDAY ACROSS EASTERN LANE AND LINN COUNTIES.
CONFIDENCE REMAINS LOW THOUGH...AS MODELS DO NOT REALLY SHOW MUCH IN
THE WAY OF A MID LEVEL TRIGGER.

MEANWHILE...BETWEEN THE INCREASE IN MID AND UPPER LEVEL CLOUDS
SPREADING NORTHWARD AND STRENGTHENING LOW LEVEL ONSHORE FLOW THROUGH
EARLY NEXT WEEK...EXPECT HIGH TEMPERATURES TO TREND DOWNWARD SEVERAL
DEGREES EACH DAY THROUGH EARLY NEXT WEEK. UNFORTUNATELY...NOT SURE
THERE WILL BE ONE DAY WHERE WE CAN SAY IT IS GOING TO FEEL
NOTICEABLY BETTER THAN THE DAY BEFORE...BUT THE GOOD NEWS IS THAT BY
THE TIME EARLY NEXT WEEK ROLES AROUND...IT WILL BE NOTICEABLY COOLER
THAN THE TRIPLE DIGIT HEAT OF YESTERDAY AND TODAY.  TW/NEUMAN

&&


.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...MONDAY NIGHT
THROUGH FRIDAY...AN UPPER LEVEL TROUGH WILL GRADUALLY APPROACH THE
REGION FROM THE NORTHWEST. CONFIDENCE IS RELATIVELY HIGH THAT MORE
SEASONAL AVERAGE TEMPERATURES AND PERIODS OF MORNING CLOUDS AND
AFTERNOON SUNSHINE WILL RETURN TOWARDS THE MIDDLE OF THE WEEK.
MODELS CONTINUE TO WAVER ON THUNDERSTORM CHANCES NEAR THE CASCADE
CREST EARLY NEXT WEEK. GENERALLY KEPT THE SLIGHT CHANCE MENTION
GOING GIVEN UNCERTAINTY. IN ADDITION...MODELS SUGGEST SHOWERS MAY
SPREAD INTO AT LEAST FAR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
LATER IN THE WEEK. CONFIDENCE REMAINS LOW IN THIS SCENARIO...BUT
INTRODUCED SLIGHT CHANCE POPS ACROSS OUR NORTHWEST ZONES AS A
RESULT. /NEUMAN


&&


.AVIATION...INLAND VFR WILL PREVAIL ALTHOUGH THERE WILL BE AREAS
OF SMOKE MAINLY ABOVE FL080 NEAR AND ALONG THE CASCADES. HAZY
CONDITIONS ALONG THE COAST WITH STRATUS LIKELY TO BREAK UP NEAR KAST
OVER THE NEXT COUPLE HOURS. ALSO EXPECT GUSTS MAINLY 20 TO 25 KT
THERE WITH LOCALIZED 25 TO 30 KT CLOSER TO FLORENCE. NOT SURE
ABOUT COASTAL CONDITIONS TONIGHT AS MODEL GUIDANCE INDICATES VERY
DRY CONDITIONS REMAIN...BUT MAY GO FOR A PERSISTENCE FORECAST AS
A FIRST THOUGHT.

KPDX AND APPROACHES...VFR CONDITIONS TODAY AND TONIGHT.

&&

.MARINE...NO CHANGES...PREVIOUS DISCUSSION FOLLOWS. HIGH PRES
LINGERING OVER THE OFFSHORE WATERS THROUGH SUN WILL KEEP N WINDS
BLOWING OVER THE COASTAL WATERS THROUGH THE WEEKEND. EXPECT THE
WINDS TO PICK UP SOME LATER TODAY AS THE TROUGH OF LOW PRES OVER
WESTERN OREGON MOVES FURTHER INLAND...RESULTING IN WIND GUSTS
RISING INTO THE 20 TO 25 KT RANGE FROM LATE TODAY INTO SUN. SEAS
WILL REMAIN DOMINATED BY N TO NW WIND WAVES AND FRESH
SWELL...KEEPING SEAS STEEP AND AT TIMES NECESSITATING AN ADVISORY
FOR HAZARDOUS SEAS MAINLY DURING LATE AFTERNOON TO OVERNIGHT
HOURS.

THE HIGH PRES WEAKENS BY LATE SUN AND MON...ALLOWING A WEAK COLD
FRONT TO MOVE S INTO THE WATERS LATE MON. SYSTEM LOOKS WEAK ENOUGH
TO ALLOW WINDS AND SEAS TO DROP BELOW SMALL CRAFT CRITERIA.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...EXCESSIVE HEAT WARNING UNTIL 9 PM PDT THIS EVENING FOR CENTRAL
     COLUMBIA RIVER GORGE-CENTRAL WILLAMETTE VALLEY-GREATER
     PORTLAND METRO AREA-SOUTH WILLAMETTE VALLEY-UPPER HOOD
     RIVER VALLEY-WESTERN COLUMBIA RIVER GORGE.

     RED FLAG WARNING UNTIL 10 PM PDT SATURDAY FOR CENTRAL OREGON
     CASCADE FOOTHILLS-EAST SLOPES OF THE CENTRAL OREGON COAST
     RANGE-MT. HOOD NATIONAL FOREST WEST OF CASCADE CREST-NORTH
     OREGON CASCADE FOOTHILLS-NORTH OREGON COAST RANGE-
     WILLAMETTE NATIONAL FOREST-WILLAMETTE VALLEY.

     HEAT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR CASCADE FOOTHILLS
     IN LANE COUNTY-CENTRAL COAST RANGE OF WESTERN OREGON-COAST
     RANGE OF NORTHWEST OREGON-LOWER COLUMBIA-NORTHERN OREGON
     CASCADE FOOTHILLS.

WA...EXCESSIVE HEAT WARNING UNTIL 9 PM PDT THIS EVENING FOR CENTRAL
     COLUMBIA RIVER GORGE-GREATER VANCOUVER AREA-WESTERN
     COLUMBIA RIVER GORGE.

     RED FLAG WARNING UNTIL 10 PM PDT SATURDAY FOR CLARK COUNTY
     LOWLANDS-EAST WILLAPA HILLS-EXTREME SOUTH WASHINGTON
     CASCADES AND FOOTHILLS.

     HEAT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR I-5 CORRIDOR IN
     COWLITZ COUNTY.

PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 2 PM THIS AFTERNOON TO 5 AM
     PDT SUNDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 2 PM THIS
     AFTERNOON TO 7 AM PDT SATURDAY FOR COASTAL WATERS FROM CASCADE
     HEAD OR TO FLORENCE OR OUT 60 NM.

&&

$$

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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