Excessive Heat in Oregon, July 1, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
906 AM PDT TUE JUL  1 2014

.SYNOPSIS...AN UPPER LEVEL RIDGE AND OFFSHORE WINDS WILL KEEP SKIES
MOSTLY CLEAR TODAY WITH HOT TEMPERATURES OVER SOUTHWEST WASHINGTON
AND NORTHWEST OREGON...THE WARMEST OF THE YEAR SO FAR IN MANY AREAS.
A WEAK SYSTEM WILL FLATTEN THE RIDGE TONIGHT WITH ONSHORE WINDS
BRINGING SUBSTANTIAL COOLING TO THE COAST AND MODERATE COOLING
INLAND. THERE IS ALSO A SLIGHT CHANCE OF THUNDERSTORMS TO THE HIGHER
CASCADES TONIGHT INTO WEDNESDAY. ONSHORE FLOW WILL PERSIST FOR THE
REST OF THE WEEK...WITH A DEEPER MARINE PUSH WEDNESDAY NIGHT AND
THURSDAY. A BROAD UPPER TROUGH WILL RESULT IN MORE SEASONAL WEATHER
THURSDAY THROUGH NEXT WEEKEND.
&&

.SHORT TERM...SKIES WERE CLEAR ACROSS SOUTHWEST WASHINGTON AND
NORTHWEST OREGON WITH OFFSHORE WINDS THROUGH THE GORGE AND ACROSS THE
HIGHER TERRAIN...WHICH WILL BRING THE WARMEST DAY OF THE YEAR SO FAR
TO MANY PARTS OF SOUTHWEST WASHINGTON AND NORTHWEST OREGON TODAY.
WINDS HAVE GUSTED INTO THE 20S IN THE HIGHER TERRAIN AND THE
GORGE...WITH MID 30S NEAR CROWN POINT. THE HEAT ADVISORY WILL BE
CONTINUED. 850 MB TEMPS STILL SUPPORT HIGHS INLAND CLOSE TO 97
DEGREES...WITH 80S TO NEAR 90 POSSIBLE AT MUCH OF THE COAST.

THE HEAT WILL LAST JUST ONE DAY AS SEVERAL CHANGES ARE EXPECTED
TONIGHT AND WEDNESDAY. WATER VAPOR AND INFRARED SATELLITE IMAGERY
SHOW SOME MID CLOUD ASSOCIATED WITH A WEAK DISTURBANCE IN NORTHERN
CALIFORNIA THAT THE MODELS ARE FORECASTING WILL LIFT NORTH THROUGH
CENTRAL OREGON AND WASHINGTON...BRUSHING OUR CASCADE ZONES TONIGHT
AND WEDNESDAY MORNING WITH AN ISOLATED SHOWER OR THUNDERSTORM.

THERE IS ALSO A WEAKENING FRONTAL BAND OUT NEAR 130W THIS MORNING
THAT IS FORECAST TO APPROACH THE COAST TONIGHT...PULL SOME STRATUS
CURRENTLY ALONG THE SOUTH OREGON COAST NORTHWARD ALONG OUR COAST
TONIGHT AND WEDNESDAY MORNING...AND PERHAPS PRODUCE SOME PATCHY
DRIZZLE NEAR THE COAST. THIS WILL LIKELY ALSO INITIATE A SOUTHWEST
MARINE PUSH UP ALONG THE COAST AND UP THROUGH THE COASTAL GAP NEAR
EUGENE AND UP THROUGH THE WILLAMETTE VALLEY TONIGHT AND WEDNESDAY
MORNING. THIS WILL BRING SUBSTANTIAL COOLING TO THE COAST AND INLAND
AREAS...WITH COASTAL AREAS CLOSER TO 60...AND INLAND AREAS WILL
PROBABLY BE BELOW 80.

THE RESULTING SOUTHWEST FLOW ALOFT WILL CONTINUE WEDNESDAY NIGHT AND
THURSDAY...MAINTAINING THE ONSHORE FLOW AND DEEP MARINE LAYER. THE
LOW CLOUDS SHOULD THIN AND BREAK OUT MID AFTERNOON OR SO ON
WEDNESDAY...THEN FILL BACK IN INLAND ON WEDNESDAY NIGHT...AND CLEAR
AGAIN THURSDAY AFTERNOON. TEMPS INLAND THURSDAY AFTERNOON WILL LIKELY
REMAIN IN THE 70S. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. THURSDAY NIGHT
THROUGH MONDAY...A BROAD UPPER LEVEL TROUGH IS EXPECTED TO REMAIN
OVER THE PAC NW FROM THU THROUGH EARLY NEXT WEEK. THIS WILL RESULT
IN PERSISTENT ONSHORE FLOW AND MARINE CLOUDS THROUGH MOST OF THE
EXTENDED FCST PERIOD. IT APPEARS THAT A WEAKENING FRONTAL SYSTEM MAY
HOLD TOGETHER ENOUGH TO BRING SOME LIGHT SHOWERS LATER SAT INTO SUN
ALONG THE S WA AND N OR COAST...AND POSSIBLY FURTHER INLAND AS WELL.
CONFIDENCE IS NOT HIGH...SO WILL ONLY CHANCE POPS OR LOWER AT THIS
TIME. OTHER THAN THIS WEAK SYSTEM...IT APPEARS THAT CONDITIONS WILL
BE MOSTLY DRY WITH A TYPICAL SUMMERTIME MORNING CLOUDS GIVING WAY TO
AFTERNOON SUN PATTERN. TEMPERATURES SHOULD RUN NEAR OR JUST BELOW
SEASONAL NORMS THROUGH LONG TERM PERIOD. PYLE &&

.AVIATION...VFR PREVAILS TODAY WITH MOSTLY CLEAR SKIES. EAST WINDS
WILL GRADUALLY INCREASE THROUGH THE GORGE. EXPECT GUSTS NEAR 20-25 KT
THROUGH MIDDAY TODAY THROUGH THE GORGE...PORTLAND METRO AREA...AND
COAST RANGE AS EASTERLY PRESSURE GRADIENT TIGHTENS. WINDS WILL TURN
MORE ONSHORE THIS TONIGHT STARTING AT THE COAST...AND MAY SEE MVFR
CONDITIONS DEVELOP ALONG THE COAST AROUND 06Z AROUND KONP AND
SPREADING UP THE COAST TO KAST AROUND 09Z WED.

KPDX AND APPROACHES...VFR UNDER CLEAR SKIES NEXT 24 HOURS. POTENTIAL
FOR LLWS AROUND 15-20 KT THROUGH 18Z WITH INCREASING E FLOW AND LIGHT
SFC WINDS...BUT SFC WINDS INCREASE THIS AFTERNOON. WINDS EASE AND
TURN MORE WESTERLY AFT 12Z WED. CULLEN
&&

.MARINE...A THERMALLY INDUCED TROUGH OF LOW PRES REMAINS ALONG THE
OREGON COAST THIS MORNING...AND WILL SHIFT INLAND LATER TODAY.
NORTHERLY WINDS OVER THE WATERS WILL REMAIN AROUND 10-15 KT WITH A
FEW GUSTS NEAR 20 KT TODAY. THERE WILL BE SOME SUBTLE CHANGES IN THE
SURFACE PRESSURE PATTERN LATE THIS AFTERNOON THROUGH WED...WITH A
SHIFT TO LIGHTER W-NW WINDS. THE NEXT CHANCE FOR SMALL CRAFT ADVISORY
WINDS WILL COME TOWARDS THE END OF THE WEEK.

WIND WAVES CONTINUE TO BE A NEARLY DOMINANT FACTOR OF THE OVERALL
SEAS SO IT MAY BECOME MORE DIFFICULT TO DISCERN FRESH SWELL FROM WIND
WAVES. SEAS ARE AROUND 4 TO 6 FT...AND WILL REMAIN IN THIS RANGE
THROUGH THE REST OF THE WEEK.	CULLEN
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HEAT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR CASCADE FOOTHILLS
     IN LANE COUNTY-CENTRAL COAST RANGE OF WESTERN OREGON-
     CENTRAL COLUMBIA RIVER GORGE-CENTRAL WILLAMETTE VALLEY-
     COAST RANGE OF NORTHWEST OREGON-GREATER PORTLAND METRO AREA-
     LOWER COLUMBIA-NORTHERN OREGON CASCADE FOOTHILLS-SOUTH
     WILLAMETTE VALLEY-WESTERN COLUMBIA RIVER GORGE.

WA...HEAT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR CENTRAL COLUMBIA
     RIVER GORGE-GREATER VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ
     COUNTY-SOUTH WASHINGTON CASCADE FOOTHILLS-WESTERN COLUMBIA
     RIVER GORGE-WILLAPA HILLS.

PZ...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10 AM
     PDT THIS MORNING.

&&

MORE WEATHER INFORMATION ONLINE AT...
    HTTP://WEATHER.GOV/PORTLAND

INTERACT WITH US VIA SOCIAL MEDIA
    WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
    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.