000 
FXUS66 KPQR 280354
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
900 PM PDT FRI JUL 27 2007

.SYNOPSIS...AN UPPER LEVEL TROUGH REMAINS OVER THE GULF ALASKA GIVING
WEAK SOUTHWEST FLOW ALOFT OVER THE PACIFIC NORTHWEST. AN UPPER LEVEL
RIDGE WILL CONTINUE OVER THE ROCKY MOUNTAIN REGION. WEAK ONSHORE FLOW
CONTINUES AS HIGHER PRESSURE BUILDS BRIEFLY OVER THE PACIFIC
NORTHWEST. ONSHORE FLOW WILL INCREASE OVER THE WEEKEND AS THE
OFFSHORE UPPER TROUGH EDGES TOWARD THE COAST. SOME DRIZZLE OR LIGHT
RAIN IS POSSIBLE NEAR THE COAST LATER IN THE WEEKEND AS A WEAK FRONT
PASSES BY...MOSTLY TO THE NORTH. HIGH PRESSURE IS EXPECTED TO REBUILD
OVER THE PACIFIC NORTHWEST NEXT WEEK FOR WARMER CONDITIONS.
&&

.SHORT TERM...LOW CLOUDS HAVE CLEARED ALL AREAS EXCEPT FOR A STRIP
OF CLOUDS ALONG THE COAST. EXPECT MARINE INVERSION LATE TONIGHT/SAT
MORNING TO BE SIMILAR TO TODAY. CLOUDS SHOULD BURN OFF OVER THE
INLAND AREAS TOMORROW BUT EXPECT CLOUDS TO REMAIN ALONG THE COAST
MOST OF THE DAY AS WEAK FRONT APPROACHES. ON SUNDAY UPPER TROUGH
BEGINS TO SHIFT EAST AND THIS WILL DEEPEN MARINE LAYER AND INCREASE
ONSHORE FLOW FOR COOLER WEATHER. MODELS CONTINUE TO MOVE UPPER TROUGH
TO THE NE ON MONDAY AND WITH A WARMING TREND FORECAST AS THE UPPER
RIDGE BUILDS IN. LIKENS

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...MODELS ARE IN
PRETTY GOOD AGREEMENT ON BUILDING THE RIDGE IN WITH HOT WEATHER
DEVELOPING BY WED OR THURSDAY. WE COULD SEE SOME MID LEVEL MOISTURE
BEGIN TO MOVE IN FROM THE SOUTH THURSDAY AND FRIDAY BUT CURRENT
MODELS DO NOT SHOW THIS. WILL HAVE TO WATCH FOR POSSIBLE CONVECTION
IN THE CASCADES LATE NEXT WEEK.
&&

.AVIATION...ONSHORE FLOW AND INCREASING MOISTURE OVER THE COASTAL
WATERS BRINGING MVFR CIGS TO THE COAST. STRATUS SPREADING OVER MUCH
OF THE NORTH COAST AND COAST RANGE AND SHOULD FILL-IN ON THE CENTRAL
COAST PER SATELLITE TRENDS. THE APPROACH OF AN UPPER TROUGH AND A
WEAKENING SURFACE FRONT COMBINED WITH A WEAK EMBEDDED SHORTWAVE
TIMED TO NEAR THE COAST AROUND 12Z COULD INDICATE THE DEEPEN OF THE
MOIST LAYER. THIS WOULD AID IN PUSHING THE STRATUS INLAND.  HOWEVER
THE SURFACE ONSHORE GRADIENT WEAKENS WHICH SHOULD LIMIT THE STRATUS
PUSH INLAND.  ALSO GIVEN THE DRIER AIR MASS...EXPECT THE STRATUS
PUSH UP THE COLUMBIA RIVER TO THE KPDX AREA GIVING MVFR CIG AROUND
12Z-17Z AND MAYBE A BRIEF MVFR CIG UP VALLEY TO KSLE.
&&

.MARINE...FAIRLY LIGHT PRES GRADIENTS TODAY THROUGH SAT KEEPING
WINDS BELOW SMALL CRAFT ADVISORY CRITERIA. SEAS WILL BE AROUND 5 FT.
THE THERMAL TROUGH STRENGTHENS OVER NORTHERN CALIFORNIA AND SOUTH
OREGON COAST EARLY NEXT WEEK FOR INCREASING NORTHERLY WINDS
ESPECIALLY OVER THE CENTRAL OREGON WATERS. SMALL CRAFT WINDS ARE
POSSIBLE.
&&

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

.PRELIMINARY POINT POPS (PROBABILITY OF MEASURABLE PRECIPITATION)
AST -1221-    PDX --111-    SLE --111-    EUG ---1--

$$

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.