SFOAFDEKA (09/06/08 1500)

FXUS66 KEKA 062201
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
300 PM PDT SAT SEP 6 2008

.SYNOPSIS...WEAKENING HIGH PRESSURE WILL BRING MORE SEASONABLE 
TEMPERATURES FOR INTERIOR LOCATIONS ACROSS NORTHWEST CALIFORNIA INTO 
NEXT WEEK. THE IMMEDIATE COASTAL AREAS WILL SEE THE RETURN OF LOW 
CLOUDS AND FOG IN THE LATE NIGHTS AND EARLY MORNINGS BEGINNING 
TONIGHT.  

&&

.SHORT TERM...UPPER LEVEL RIDGE THAT HAS BEEN DOMINATING THE WEATHER 
ACROSS NORTHWEST CALIFORNIA OVER THE PAST WEEK WILL SLOWLY BEGIN TO 
FLATTEN AS AN UPPER LEVEL LOW IN THE GULF OF ALASKA SWINGS OVER THE 
TOP OF THE RIDGE. ANOTHER WEAK SHORTWAVE WILL SWING DOWN THE EAST 
SIDE...LOWERING HEIGHTS OVER OUR REGION BEGINNING TOMORROW. A 
NOTICEABLE COOLING TREND CAN BE EXPECTED BEGINNING SUNDAY INTO 
MONDAY WITH MORE SEASONABLE TEMPS EXPECTED FOR NEXT WEEK. 

THE OFFSHORE FLOW HAS BEEN ABLE TO CARRY SMOKE FROM FIRES OVER 
SOUTHEASTERN DEL NORTE AND SISKIYOU COUNTIES TOWARDS THE COAST AND 
OFFSHORE...BUT MOST OF THIS SMOKE LAYER APPEARS TO BE WELL ALOFT AND 
THIN. HAVE ONLY MENTIONED IT OVER SOUTHERN DEL NORTE WHERE SMOKE IS 
THE THICKEST. 

COASTAL STRATUS OVERNIGHT WILL BE A LITTLE MORE TRICKY. MODEL RH 
FORECASTS ARE INDICATING THAT THE STRATUS BANK THAT IS FILLED INTO 
MOST OF THE OREGON COAST AND THE FAR OFFSHORE WATERS WILL GRADUALLY 
CREEP TOWARDS THE COAST OVERNIGHT. HOWEVER...THERE APPEARS TO BE 
ENOUGH OFFSHORE FLOW STILL PRESENT TO KEEP THE DEL NORTE COAST 
MOSTLY CLEAR WITH PATCHY RADIATIONAL FOG WHILE THE STRATUS FILLS 
INTO THE HUMBOLDT BAY AND EEL RIVER DELTA. THERE APPEARS TO BE SOME 
DIFFERENCE AS TO HOW MUCH STRATUS WILL FILL INTO THE DEL NORTE AND 
MENDOCINO COASTS SUNDAY AND MONDAY NIGHT...BUT HAVE LEANED MORE WITH 
CLIMATOLOGY AS EXPECT THE SHORTWAVE TO HELP PUSH THE STRATUS TOWARDS 
THE COAST. ALM


.LONG TERM...WED THROUGH SAT...MODELS CONTINUE TO SHOW A LONG WAVE 
RIDGE DOMINATING OVER THE EASTERN PACIFIC THROUGH NEXT WEEK. ALL THE 
MEDIUM RANGE MODELS SHOW GOOD AGREEMENT THROUGH THE WEEK AS A BAGGY 
UPPER TROUGH/CLOSED LOW DEVELOPS ALONG AND OVER SOUTHERN CALIFORNIA. 
THIS WILL LIKELY KEEP NORTHWEST CALIFORNIA UNDER A RIDGE AND STABLE
WEATHER PATTERN. INLAND AREAS SHOULD CONTINUE TO EXPERIENCE 
SEASONABLY WARM TEMPERATURES UNDER CLEAR SKIES AND WEAK OFFSHORE 
FLOW...WHILE COASTAL AREAS WILL MOST LIKELY CONTINUE TO SEE ABUNDANT 
SUNSHINE WITH TYPICAL NIGHT/MORNING LOW CLOUDS/FOG. DJB 

&&

.AVIATION...EXPECT GUSTY NORTHWEST WINDS AT CEC AGAIN THROUGH THIS 
EVENING WITH MAINLY LIGHT WINDS PREVAILING ELSEWHERE. MODELS REMAIN 
IN GOOD AGREEMENT IN BRINGING AN END TO VFR CONDITIONS AS BL RH 
VALUES INCREASE ALONG THE COAST. EXPECT IFR CIGS AND MVFR VIS AT ACV 
AFTER 06Z WITH IFR VIS BY SUNRISE. STRATUS WILL BUILD N ALONG THE 
REDWOOD COAST OVERNIGHT REACHING CEC AROUND SUNRISE PRODUCING TEMPO 
MVFR VIS/IFR CIGS EARLY SUN MORNING. BC   

&&

.MARINE...GALE AND HAZ SEAS WARNINGS CONTINUE OVER THE NORTHERN 
OUTER WATERS THROUGH SUNDAY AS HIGH PRESSURE OVER THE NE PAC 
CONTINUES TO INTERACT WITH LOW PRESSURE OVER CA. THE STRONG WINDS 
OVER THE OUTER WATERS WILL CONTINUE TO GENERATE STEEP SHORT-PERIOD 
SWELL THAT WILL CONTINUE TO MIGRATE INTO THE INNER WATERS WITH SMALL 
CRAFT ADVISORIES FOR SEAS ACROSS THE NORTHERN INNER WATERS THROUGH 
MONDAY. LOW PRESSURE DEVELOPING OFFSHORE OF MEXICO THIS WEEKEND WILL 
BRING A SMALL LONG-PERIOD SOUTH SWELL TO THE WATERS EARLY IN THE 
WEEK. THE LARGE WIND SEAS AND FRESH SWELL IN THE NORTHERN WATERS MAY 
MAKE THE SMALLER SOUTH SWELL HARD TO DETECT. BC 

&&

.EKA WATCHES/WARNINGS/ADVISORIES...

GALE AND HAZARDOUS SEAS WARNINGS FROM PT ST GEORGE TO CAPE MENDOCINO 
FROM 10 TO 60 NM OUT.

SMALL CRAFT ADVISORY FOR WINDS AND HAZARDOUS SEAS FROM CAPE 
MENDOCINO TO PT ARENA OUT 10 NM.

SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM PT ST GEORGE TO CAPE 
MENDOCINO OUT 10 NM.

&&



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