AREA FORECAST DISCUSSION

 
 FXUS66 KEKA 241118
 AFDEKA
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE EUREKA CA
 320 AM PST TUE NOV 24 2009
 
 .SYNOPSIS...WEAK HIGH PRESSURE WILL REMAIN ACROSS NORTHWEST 
 CALIFORNIA TODAY INTO WEDNESDAY...BRINGING DRY AND PLEASANT WEATHER. 
 LOW PRESSURE WILL APPROACH THE AREA LATE THANKSGIVING DAY...BRINGING 
 THE THREAT FOR RAIN AND SNOW ABOVE 4000 FEET. THIS SYSTEM WILL EXIT 
 THE REGION FRIDAY WITH GENERALLY DRY WEATHER EXPECTED FOR NEXT 
 WEEKEND.
 
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 .DISCUSSION...THE MAIN FORECAST CONSIDERATION CONTINUES TO BE THE 
 NEXT COLD FRONTAL PASSAGE SLATED FOR LATE TURKEY DAY/EARLY FRIDAY.
 
 AT 3 AM PST...A WEAK SHORTWAVE TRACKING TO THE NORTH OF THE STATE 
 WAS BRINGING VARIABLE HIGH CLOUDINESS TO THE FORECAST AREA BUT 
 LITTLE ELSE. CLOUDINESS SHOULD THIN OUT DURING THE MORNING WITH 
 PARTLY CLOUDY/MOSTLY SUNNY SKIES FOR THE BALANCE OF THE DAY WITH A 
 PLEASANT DAY TEMPERATURE-WISE. THE PACIFIC VAPOR PIX SHOWS THE NEXT 
 TROUGH...SITUATED WELL NORTH OF HAWAII CURRENTLY...THAT WILL 
 EVENTUALLY IMPACT THE REGION. AS THE CENTRAL LOW MOVES EAST ACROSS 
 THE SOUTHERN GULF OF ALASKA IT WILL SPIN OFF SEVERAL DISTURBANCES 
 AND HELP BREAK DOWN THE RIDGE OVER CALIFORNIA ON THANKSGIVING DAY. 
 TODAY`S MODEL RUNS ARE PERHAPS 6 HOURS FASTER IN BRINGING 
 PRECIPITATION TO NORTHWEST CAL THAN THOSE FROM YESTERDAY. EVEN 
 SO...MOST PRECIP SHOULD HOLD OFF UNTIL SUNSET OR LATER THANKSGIVING 
 DAY EXCEPT NEAR THE COAST NORTH OF THE CAPE WHERE LIGHT RAIN MAY 
 BEGIN DURING THE AFTERNOON. ACCUMULATING SNOW LEVELS WILL STILL 
 REMAIN ABOVE ALL OUR MAJOR PASSES SO THERE SHOULD BE NO WINTER 
 WEATHER TRAVEL CONCERNS FOR THOSE HEADING DOWN TO THE BAY AREA OR 
 INTO THE CENTRAL VALLEY. PRECIPITATION SHOULD END FRIDAY AFTERNOON 
 AS HIGH PRESSURE BUILDS BACK OVER THE EASTERN PACIFIC...WHICH SHOULD 
 PROVIDE ANOTHER RESPITE FROM THE WET SEASON FOR THE WEEKEND. BURGER  
 
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 .AVIATION...LIGHT OFFSHORE WINDS ARE BRINGING VFR TO ALL TAF SITES 
 THIS MORNING. A WEAK PRESSURE GRADIENT WILL CONTINUE TO BRING 
 GENERALLY LIGHT WINDS TO THE TAF SITES TODAY. VFR ARE EXPECTED TO 
 PREVAIL THIS AFTERNOON. STROZ
 
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 .MARINE...BUOY OBSERVATIONS THIS MORNING SHOW A MIXED NORTHWEST 
 SWELL, NEAR 12 SECONDS AND NEAR 15 SECONDS. THE SWELL NEAR 12 
 SECONDS WILL BECOME DOMINANT IN THE UPCOMING HOURS AND WILL BUILD TO 
 NEAR 10 FT. THEREFORE, A SCA FOR HAZARDOUS SEAS IS UP OVER ALL OF 
 THE ZONES THROUGH LATE TONIGHT. HIGH PRESSURE WILL REMAIN OVER THE 
 EASTERN PACIFIC THROUGH WEDNESDAY, PRODUCING LIGHT NORTH WINDS. A 
 NORTHWEST SWELL WILL CONTINUE TO PROPAGATE THROUGH THE WATERS 
 THROUGH MIDWEEK. MODELS ARE IN FAIRLY GOOD AGREEMENT THAT A FRONT 
 WILL MOVE ACROSS THE WATERS LATE THURSDAY. SOUTHERLY WINDS WILL 
 INCREASE AHEAD OF THE FRONT TO NEAR GALE FORCE AND REMAIN GUSTY AS 
 THEY VEER TO THE NORTHWEST BEHIND THE FRONT. SEAS WILL ALSO BECOME 
 HAZARDOUS WITH THE MAIN IMPACTS BEING WIND WAVES PRE FRONT AND A 
 LARGE NORTHWEST SWELL POST FRONT. IT`S STILL TOO EARLY TO ISSUE 
 WATCHES WITH THIS FORECAST PACKAGE. STROZ
 
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 .EKA WATCHES/WARNINGS/ADVISORIES...
 
 SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 3 AM PST WEDNESDAY FOR 
 ALL WATERS.
 
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