SFOAFDEKA (11/22/08 0403)
FXUS66 KEKA 221207
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
405 AM PST SAT NOV 22 2008
.SYNOPSIS...RAIN THIS MORNING WILL TAPER OFF TO ISOLATED SHOWERS BY
THIS AFTERNOON AS A COLD FRONT MOVES EAST OF THE REGION. DRY
CONDITIONS ARE EXPECTED THIS EVENING THROUGH TOMORROW NIGHT. A
STRONG UPPER LEVEL LOW IS EXPECTED TO DEVELOP OFF THE CALIFORNIA
COAST EARLY NEXT WEEK BRINGING ADDITIONAL WET WEATHER TO THE REGION.
&&
.SHORT TERM...TODAY THROUGH MONDAY NIGHT...A COLD FRONT NOW PUSHING
ONTO THE NORTHWEST CALIFORNIA COAST IS SPREADING RAIN TO THE
NORTHERN PORTION OF THE FORECAST AREA THIS MORNING. AFTER THE FRONT
CLEARS THE REGION LATER THIS MORNING AND THE UPPER TROUGH AXIS
PUSHES EAST...EXPECT SHOWERS TO QUICKLY TAPER OFF...WITH ISOLATED
ONLY ISOLATED SHOWERS EXPECTED OVER THE NORTHERN FORECAST AREA BY
THIS AFTERNOON. TOTAL RAINFALL AMOUNTS WILL BE ONE OR TWO TENTHS OF
AN INCH IN DEL NORTE COUNTY AND ONLY A FEW HUNDREDTHS AT BEST TOWARD
CAPE MENDOCINO.
MODELS ARE STILL IN GOOD AGREEMENT REGARDING AN AMPLIFIED RIDGE
BUILDING OVER THE WEST COAST TONIGHT. ASIDE FROM FOG ALONG THE
NORTH COAST AND IN THE NORTHERN INTERIOR VALLEYS IN THE MORNING...
SUNDAY WILL BE A FAIR DAY ACROSS THE REGION. MODELS SHOW A DEEP
TROUGH DEVELOPING AROUND 135 W BY LATE SUNDAY AFTERNOON (00Z MON).
SOLUTIONS DIVERGE HEADING INTO MONDAY...BUT WILL CONTINUE WITH THE
PREVIOUS FORECAST THINKING OF SHOWING GRADUALLY INCREASING CLOUDS
AND RAINFALL CHANCES THROUGH MONDAY NIGHT. KL
.LONG TERM...TUESDAY THROUGH FRIDAY...LITTLE CHANGE MADE TO THE LONG
TERM FORECAST THIS MORNING. MODEL CONSENSUS LOOKS BETTER REGARDING
THE TRACK OF THE CLOSED LOW THROUGH TUESDAY. BEYOND TUESDAY...
SOLUTIONS DIVERGE SIGNIFICANTLY. IT APPEARS THE MAIN UPPER LOW WILL
MOVE EAST OF THE REGION BY WEDNESDAY WITH MOST MODELS SHOWING
ANOTHER TROUGH MOVING INTO THE REGION THURSDAY OR FRIDAY. HAVE
CONTINUED WITH THE PREVIOUS FORECAST REASONING AS FAR AS RAINFALL
CHANCES ARE CONCERNED. WILL GO WITH CLIMATOLOGY VALUES FOR POPS
TUESDAY WITH ONLY SLIGHT CHANCE POPS WEDNESDAY. POPS RAMP UP INTO
CHANCE CATEGORY AGAIN BY THANKSGIVING DAY AS THE NEXT POTENTIAL
TROUGH AFFECTS THE REGION. KL
&&
.AVIATION...FRONT APPROACHING WITH MVFR CONDITIONS IN RAIN AT KCEC
AND KACV. ESTIMATE FRONT WILL PASS THROUGH CEC JUST BEFORE SUNRISE
AND WHATS LEFT OF FRONT PASS THROUGH UKI AND EASTERN TRINITY COUNTY
BEFORE NOON. MVFR CIGS AND VSBYS AND LOCAL AREAS OF IFR VSBYS WITH
FRONT ESPECIALLY NEAR AND NORTH OF FORTUNA VOR. LOW END VFR FURTHER
TO THE SOUTH WILL OBSCURE MTNS. ONCE FRONT GOES BY...ENOUGH
INSTABILITY FOR VFR CIGS IN ISOLATED SHOWERS MAINLY NORTH OF FORTUNA
VOR. DEAN
&&
.MARINE...SEAS AT BUOYS 15 AND 27 ARE STARTING TO INCREASE AS NEXT
NW SWELL TRAIN ENTERS WATERS. SEAS WILL PEAK THIS AFTERNOON NEAR
9-11 FEET. A WEAK COLD FRONT IS STARTING TO MOVE THROUGH THE
NORTHWEST COASTAL WATERS AND WHATS LEFT WILL PASS THROUGH SRN WATERS
BY MIDMORNING. HIGH PRESSURE WILL BRIEFLY BUILD BACK INTO THE REGION
BEHIND THE FRONT WITH WINDS EXPECTED TO STAY BELOW ADVISORY
CRITERIA. STILL LOTS OF UNCERTAINTY FOR NEXT WEEK AS MODELS
CONTINUE TO SHOW POOR RUN TO RUN CONSISTENCIES. LOW PRESSURE MOVES
INTO THE EASTERN PACIFIC AND NORTHERN END TRACKS TOWARD BC. SOUTHERN
END SPLITS AND SECOND SURFACE SURFACE LOW DEVELOPS ABOUT 450NM OFF
THE COAST BY SUNDAY AFTERNOON BUT EXACTLY WHERE IS STILL UNCLEAR AS
MODELS VARY FROM CLOSING THE LOW WEST OF CEC TO CLOSING IT OFF WEST
SFO. ALL MODELS DRIFT IT SE TOWARD THE COAST BUT LOCATION STILL
UNSURE. A COLD FRONT TRACKS THROUGH THE PACIFIC NORTHWEST AND INTO
THE COASTAL WATERS ABOUT TUESDAY NIGHT WITH SURFACE HIGH BUILDING
BEHIND IT AND STRONG WINDS DEVELOPING IN THE WATERS ON WED. GFS
DEVELOPS STRONG LOW IN GULF OF ALASKA WED NIGHT AND THUR WHICH ENP
TRANSLATES INTO A 15-16 FT NW SWELL TRAIN MOVING INTO COASTAL WATERS
ON FRIDAY. GIVEN LOW CONFIDENCE DUE TO MODEL INCONSISTENCIES WILL
CONTINUE TO TREND BELOW GUIDANCE VALUES FOR THE EXTENDED. DEAN
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
SCA FOR HAZARDOUS SEAS FOR PZZ450-455-470-475.
&&
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