FXUS66 KEKA 140029
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
355 PM PST SAT NOV 13 2004

.SYNOPSIS...
HIGH PRESSURE OVER THE EASTERN PACIFIC WILL CONTINUE TO 
BRING WARM CONDITIONS TO THE FORECAST AREA THROUGH SUNDAY NIGHT. 
HIGH CLOUDS WILL STREAM IN FROM A LARGE STORM SYSTEM WELL 
OFFSHORE...RESULTING IN DIMINISHED SUNSHINE NORTH OF MENDOCINO 
COUNTY ON SUNDAY. THIS STORM SYSTEM WILL BRING A COLD FRONT TO THE 
COASTAL WATERS SUNDAY NIGHT. THIS FRONT WILL SLOW DOWN AND WEAKEN AS 
IT DRIFTS ONSHORE MONDAY INTO MONDAY NIGHT. LOW PRESSURE DEVELOPING 
ALONG THE FRONT WILL KEEP A CHANCE OF RAIN TUESDAY THROUGH TUESDAY 
NIGHT...BEFORE WEAK HIGH PRESSURE BUILDS INTO THE REGION WEDNESDAY.
UNSETTLED CONDITIONS WILL RETURN DURING THE LATTER PART OF THE WEEK.

&&

.DISCUSSION...
HIGH CLOUDS HAVE STREAMED INTO THE FORECAST AREA AS THEY DRIFT OVER 
THE RIDGE OF HIGH PRESSURE OVER THE EASTERN PACIFIC. THESE CLOUDS 
ARE COURTESY OF AN IMPRESSIVE CYCLONE STRETCHING FROM THE 
INTERTROPICAL CONVERGENCE ZONE WEST OF HAWAII INTO THE YUKON 
TERRITORY OF NW CANADA. THIS RIDGE OF HIGH PRESSURE AND PERIODS OF 
HIGH CLOUDS OF VARYING DENSITY WILL RESULT IN ANOTHER WARM DAY OF 
FILTERED SUNSHINE FORECAST AREA WIDE TOMORROW...BEFORE THE FRONTAL 
BOUNDARY ASSOCIATED WITH THE IMPRESSIVE CYCLONE WASHES ONSHORE. 
BUMPED TEMPERATURES UP 1F TO 4F FORECAST AREA WIDE TOMORROW EXCEPT 
AT KCEC AND FORT BRAGG FOR SUNDAY DUE TO SLIGHTLY WARMER CONDITIONS 
TODAY AND SOME WEAK WAA COMING IN FORM THE SOUTH IN THE NEXT 24 
HOURS.

PRIMARY ALTERATIONS TO GOING FORECAST WERE WITH TIMING AND INLAND 
PENETRATION OF THE PRECIPITATION ASSOCIATED WITH THE FRONT AS IT 
MOVES INTO THE FORECAST AREA. SLEW OF MODEL SOLUTIONS TODAY VARIED 
FROM THE NOGAPS AND ETA SOLUTIONS STALLING THE FRONT AT KCEC TO THE 
UKMET AND 00Z GFS PUSHING IT INTO TRINITY COUNTY AND NORTHERN 
PORTIONS OF MENDOCINO COUNTY MONDAY INTO MONDAY NIGHT. ATTEMPTED TO
BLEND THESE SOLUTIONS...KEEPING LIKELY POPS ONLY ACROSS THE EXTREME 
NORTH AND WEST...TAPERING TO NO CHANCE WELL SOUTH. 
INTERESTINGLY...SPLIT JET FLOW THAT DEVELOPED WITH THE LAST TWO 
STORM SYSTEM AS THEY ENCOUNTERED THE WEST COAST SHOWS INDICATIONS OF 
DEVELOPING AGAIN WITH THIS NEXT SYSTEM. THE GFS 300MB WIND FIELD 
SHOWS TWO 50+KT MAXIMUMS IMPACTING ON THE WEST COAST BY 
TUESDAY...WITH ONE PUSHING INTO SOUTHERN BRITISH COLUMBIA...AND THE 
OTHER PUSHING INTO SOUTHERN CALIFORNIA. MODEL SFC OUTPUT INDICATES A 
WEAK AREA OF LOW PRESSURE DEVELOPING ALONG THE FRONTAL BOUNDARY AS 
IT DRIFTS INTO THE COAST. ON THE 12Z RUN THIS FEATURE TRACKED OVER 
THE MIDDLE OF THE CWA- ON THE 18Z RUN IT IS NOW FURTHER SOUTH. 
OVERALL UPPER LEVEL SCHEME TRACKS AN ASSOCIATED UPPER LOW ACROSS 
MENDOCINO COUNTY TUESDAY AS THE SYSTEM SPLITS. GIVEN SOUTHERN 
LOCATION OF UPPER DYNAMICS AND SOUTHERLY FLOW...EXPECT MODEL QPF TO 
TREND FURTHER SOUTH THAN CURRENTLY DEPICTED...SO TRENDED POP MAX 
ACCORDINGLY.

IN THE LONGER TERM...THE GFS SHOWS A COUPLE OF SYSTEMS QUICKLY ON 
THE HEELS OF THE MONDAY/TUESDAY SYSTEM. MAINLY FOLLOWED THE ECMWF 
FOR LONGER RANGE GUIDANCE WITH POPS(AFTER MON/TUES)...BUT WOULD NOT 
BE SURPRISED IF THIS LONG TERM FORECAST NEEDS SIGNIFICANT 
ADJUSTMENTS IN THE NEXT FEW DAYS DUE TO RUN TO RUN INCONSISTENCIES 
IN THE GLOBAL MODELS. THESE UNCERTAINTIES ARE LIKELY THE RESULT OF 
THE WIDE RANGE OF LATITUDES ENCOMPASSED BY THE SPLIT AND SPLITTING 
JET(S). GENERALLY SPEAKING...IT DOES APPEAR THAT A COOLER AIRMASS 
WILL BE OVER THE AREA BY MIDWEEK...SO THE HIGH ELEVATION SNOW MELT 
WILL LIKELY COME TO AN END.

&&

.EKA WATCHES/WARNINGS/ADVISORIES...

SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS TODAY THROUGH MONDAY 
FROM CAPE MENDOCINO TO POINT SAINT GEORGE OUT 60NM

SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS TODAY THROUGH SUNDAY 
FROM CAPE MENDOCINO TO POINT ARENA OUT 60NM

&&

$$
LUTZ