000
FXUS66 KPQR 141043
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
342 AM PDT FRI JUN 14 2013

.SYNOPSIS...SHOWERS WILL EASE THIS MORNING AS HIGH PRESSURE BUILDS
OVER THE AREA. DRY AND WARMER WEATHER IS EXPECTED THIS WEEKEND WITH
THE POSSIBILITY OF MOUNTAIN THUNDERSTORMS IN THE AFTERNOON AS A DEEP
TROUGH OF LOW PRES DIGS IN OFFSHORE. THE LOW WILL SLOWLY APPROACH THE
COAST EARLY NEXT WEEK AND FINALLY MOVE ACROSS OREGON MIDWEEK.

&&

.SHORT TERM...SHOWERS ARE RAPIDLY DECREASING EARLY THIS MORNING AS
HIGH PRESSURE BUILDS OVER THE AREA. THE UPPER LOW THAT BROUGHT
UNSETTLED WEATHER TO THE REGION THE PAST FEW DAYS HAS MOVED EAST OF
THE CASCADES. RADAR SHOWS A FEW SHOWERS OVER THE CASCADES..BUT THEY
ARE DISSIPATING RAPIDLY.

MODELS PERSIST IN FORECASTING POSSIBLE SHOWERS ACROSS THE NW CORNER
OF THE FORECAST AREA THROUGH THIS AFTERNOON. LINGERING LOW LEVEL
MOISTURE COMBINED WITH WEAK ISENTROPIC LIFT MAY BE ENOUGH TO GENERATE
THESE SHOWERS SO HAVE CONTINUED THE SLIGHT CHANCE MAINLY FOR THE
NORTH COAST AND COAST RANGE. SKIES SHOULD CLEAR THIS AFTERNOON AT
LEAST PARTLY AND TEMPERATURES WILL WARM CLOSE TO NORMAL. CLOUDS WILL
HANG AROUND LONGER ACROSS THE NW CORNER.

500 MB HEIGHTS WILL INCREASE OVER THE REGION SATURDAY AS AN UPPER LOW
MOVES INTO THE NE PACIFIC....AND DAYTIME TEMPERATURES WILL WARM TO
ABOVE NORMAL...AT LEAST INLAND. MODELS SUGGEST THAT A REX BLOCK WILL
DEVELOP OVER THE EAST PACIFIC THIS WEEKEND AND KEEP THE UPPER LOW
OFFSHORE THROUGH AT LEAST MONDAY. THIS SHOULD KEEP THE WEEKEND MOSTLY
DRY ALTHOUGH THERE IS POTENTIAL FOR CONVECTION AND SHOWERS OVER THE
MOUNTAINS IN THE AFTERNOONS. THE THREAT FOR THUNDERSTORMS IS GREATEST
ON SUNDAY WHEN THE FLOW AT MOST LEVELS BECOME SW.

IT ALSO LOOKS LIKE A SW MARINE PUSH ENSUES SAT NIGHT...RESULTING IN
COOLER AND CLOUDIER CONDITIONS FOR SUNDAY.

.LONG TERM...AN UPPER LOW WILL SLOWLY PUSH INLAND EARLY IN THE WEEK
RESULTING IN COOL AND SHOWERY WEATHER...AND A THREAT OF MOUNTAIN
THUNDERSTORMS.DRIER CONDITIONS ARE EXPECTED LATE NEXT WEEK AS ANOTHER
SHORTWAVE UPPER RIDGE WILL PUSH ACROSS THE REGION.

&&

.AVIATION...WEAK ONSHORE FLOW CONTINUES OVER THE COAST AND NORTH
INTERIOR FOR PATCHY MVFR CONDITIONS THROUGH 16Z TO 18Z. AREAS IN
THE WILLAMETTE VALLEY THAT CLEARED LATE THU NIGHT WILL SEE
VARIABLE IFR/MVFR CONDITIONS AS INTERMITTENT FOG AND LOW CLOUDS
DEVELOP.
NORTHERLY FLOW INCREASES MID TO LATE MORNING AND CONDITIONS AT TAF
SITES RETURN TO VFR.

KPDX AND APPROACHES...MOISTURE MOVING DOWN THE COLUMBIA COULD KEEP
MVFR CONDITIONS NEAR THE AIRPORT THROUGH ABOUT 15Z-17Z. CONDITIONS
WILL IMPROVE TO VFR AS NORTHERLY FLOW DEVELOPS BY 19Z.

&&

.MARINE...HIGH PRESSURE BUILDS OVER THE WATERS TODAY WITH
THERMALLY INDUCED LOW PRESSURE OVER NORTHERN CALIF. THIS GENERATES
NORTHERLY FLOW OVER THE WATERS THROUGH SATURDAY. EXPECT BENIGN
CONDITIONS FOR THE NEXT FEW DAYS. WINDS MAY GUST TO 20 KT AT TIMES
OVER THE CENTRAL OR WATERS THIS AFTERNOON AND EVENING. SEAS
REMAIN BELOW 5 FT INTO EARLY NEXT WEEK.

ANOTHER LOW PRESSURE SYSTEM MOVES INTO THE WATERS THIS WEEKEND AND
REMAINS NEARLY STATIONARY THROUGH THE FIRST HALF OF NEXT WEEK. DO
NOT EXPECT ANY SIGNIFICANT IMPACTS FROM THIS SYSTEM. WINDS SHIFT
FROM LIGHT NORTHERLY BACK TO LIGHT SOUTHERLY BY EARLY MONDAY AS
THE LOW PRESSURE NEARS THE WATERS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.

&&

$$

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

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.