FXUS66 KEKA 201121
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
421 AM PDT SAT SEP 20 2008
.SYNOPSIS...WEAK HIGH PRESSURE WILL BUILD OVER NORTHERN CALIFORNIA 
TODAY AND HOLD THROUGH MIDDAY SUNDAY BEFORE WEAKENING. LATE SUNDAY 
NIGHT INCREASING CLOUDS AS A WEAK UPPER LEVEL TROUGH WILL MOVE 
ACROSS THE REGION.
&&
.SHORT TERM...TODAY THROUGH MONDAY...THE GFS AND ECMWF MODELS ARE
IN GOOD AGREEMENT DURING THIS TIME PERIOD. OVERNIGHT...WIDESPREAD
SC CEILINGS AND AREAS OF VALLEY FOG WAS INDICATED BY SATELLITE
IMAGERY. AS THE TROUGH LIFTS TO THE NORTHEAST AND WEAK RIDGING
BUILDS OVER NORTHERN CALIFORNIA...THE CLOUDS WILL GRADUALLY BECOME
SCATTERED AND FOR INLAND LOCATIONS...THE SKIES WILL BECOME CLEAR.
THIS WILL MEAN A WARMING AND DRYING TREND FOR THE INTERIOR. THE
COAST WILL REMAIN UNDER THE INFLUENCE OF THE MARINE LAYER...AND
THE LOW CLOUDS AND PATCHY FOG WILL RETURN SATURDAY NIGHT INTO
SUNDAY MORNING. SUNDAY NIGHT A WEAK TROUGH WILL MOVE ACROSS THE
REGION. OTHER THAN AN INCREASE IN CLOUDS...NO WEATHER IS EXPECTED.
MONDAY A SLIGHTLY STRONGER RIDGE WILL BUILD AND MOVE ACROSS THE
REGION. KENNEDY
.LONG TERM...TUESDAY THROUGH FRIDAY...THE UPPER LEVEL RIDGE WILL 
MOVE TO THE EAST AS AN UPPER LEVEL TROUGH APPROACHES THE PACIFIC 
NORTHWEST. THE INLAND WARMING TREND WILL CONTINUE THROUGH TUESDAY. 
THE MODELS DIFFER ON THE STRENGTH OF THIS TROUGH. THE ECMWF HAD A 
DEEPER TROUGH AND EXTENDED THE PRECIPITATION FURTHER SOUTH THAN THE 
GFS MODEL. AS A COMPROMISE...DID INCREASE THE POPS TO SLIGHT CHANCE 
OF PRECIPITATION FOR WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT 
NORTH OF KLAMATH. THE WEAK COLD FRONT ASSOCIATED WITH THIS SYSTEM 
WILL BRING COOLER TEMPERATURES TO THE NORTHERN HALF OF THE CWA. THEN 
FOR THURSDAY AND FRIDAY A WEAK RIDGE BUILD OVER THE REGION...BRINGING A 
DRY PATTERN AND SEASON TEMPERATURES. THE ABSENCE OF A STRONG 
OFFSHORE FLOW WILL CONTINUE THE USUAL REGIMEN OF LATE NIGHT AND 
EARLY MORNING LOW CLOUDS ALONG THE COAST WITH PARTIAL CLEARING EACH 
AFTERNOON.  KENNEDY
&&
.AVIATION...CIGS EARLY THIS MORNING CONTINUE TO REMAIN 
VFR...GENERALLY BETWEEN 030 AND 050 ACROSS THE REGION. THOUGH NO 
SITES HAVE REPORTED ANY LOWERED VSBYS YET...WITH YESTERDAYS LIGHT 
PRECIP ACROSS THE REGION...MOST AREAS CAN EXPECT SOME BRIEF PATCHY 
MVFR FOG AROUND SUNRISE...ESPECIALLY IN VALLEY LOCATIONS AND ALONG 
THE COAST. 
LIGHT AND VARIABLE WINDS THIS MORNING WILL SHIFT TO THE N AND NW BY 
THE AFTERNOON HOURS AS HIGH PRESSURE STRENGTHENS OVER THE EAST 
PACIFIC. WITH FLOW REMAINING GENERALLY LIGHT THROUGH THIS 
AFTERNOON...ITS LIKELY THAT SCT-BKN 030-050 CIGS WILL CONTINUE 
THROUGH THE DAY ESPECIALLY OVER COASTAL HILLS. ALM
&&
.MARINE...W-NW SWELL TRAIN BEHIND THE UPPER LOW PASSAGE CONTINUES TO 
AFFECT THE REGION WITH SEAS RUNNING BETWEEN 4 TO 6 FT THIS MORNING. 
WAVE RIDER BUOYS CONTINUE TO SHOW A SOUTHERLY SWELL OF 2 TO 3 FT 
MOVING THROUGH THE WATERS. SEAS WILL PEAK THIS MORNING AT THEIR 
CURRENT HEIGHTS AND GRADUALLY SUBSIDE THROUGH THE REMAINDER OF THE 
DAY BACK DOWN TO 2 TO 3 FT...WITH SEAS REMAINING MIXED AS SOUTHERLY 
SWELL CONTINUES. 
N-NW WINDS WILL INCREASE THROUGH THE DAY AS HIGH PRESSURE BUILDS 
OVER THE EAST PACIFIC. WINDS ARE EXPECTED TO INCREASE TO SCA LEVELS 
OVER THE OUTER WATERS LATER ON SUNDAY AS STRONGER HIGH PRESSURE 
BUILDS INTO THE PAC NW BEHIND ANOTHER WEAK FRONT. MODELS HAVE BEEN 
INCONSISTENT WITH STRENGTH OF WINDS IN THE MON-WED TIME FRAME...BUT 
SFC PRESSURE PATTERN CONTINUES TO LOOKS GOOD FOR HIGH END SCA 
CONDITIONS AND HAVE CONTINUED TO INDICATED GALE FORCE GUSTS FOR THE 
OUTER WATERS. SCA CONDITIONS ARE EXPECTED TO CONTINUE OVER THE OUTER 
COASTAL WATERS THROUGH THE MIDDLE OF NEXT WEEK. ALM
&&
.EKA WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
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