Area Forecast Discussion
Issued by NWS Eureka, CA

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000
FXUS66 KEKA 022208
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
308 PM PDT WED SEP 2 2015

.SYNOPSIS...NEAR NORMAL TEMPERATURES WILL CONTINUE ACROSS THE
REGION THIS WEEK AS A LOW PRESSURE TROUGH PERSIST ACROSS THE WEST
COAST. A FEW LIGHT SHOWERS OR ISOLATED THUNDERSTORMS ARE POSSIBLE
OVER THE INTERIOR ON FRIDAY.


&&

.DISCUSSION...AN UPPER LEVEL LOW PRESSURE TROUGH OVER THE NORTH
WEST PACIFIC PRODUCED A FEW LIGHT SHOWERS PRIMARILY ACROSS THE
NORTHERN AREAS THIS MORNING. DRIER CONDITIONS WILL PREVAIL ACROSS
THE REGION THURSDAY WITH NEAR NORMAL TEMPERATURES. AN UPPER LEVEL
LOW PRESSURE TROUGH WILL MOVE ACROSS THE REGION THURSDAY NIGHT AND
FRIDAY. THE LOW PRESSURE TROUGH WILL PRODUCE A SLIGHT CHANCE FOR
SHOWERS PRIMARILY ACROSS THE NORTHERN AND INLAND AREAS FRIDAY
AFTERNOON AND FRIDAY NIGHT. A FEW ISOLATED THUNDERSTORMS ARE
POSSIBLE ACROSS NORTHERN TRINITY COUNTY AND THE YOLLA BOLLYS LATE
FRIDAY AFTERNOON. NEAR NORMAL TEMPERATURES WILL THROUGH THIS
WEEKEND. TEMPERATURES WILL INCREASE OVER THE INTERIOR NEXT WEEK.

&&

.AVIATION...MID TO UPPER CLOUD COVER ASSOCIATED WITH A WEAK FRONT
WILL CONTINUE TO IMPACT PARTS OF NORTHERN CALIFORNIA TODAY. EXPECT
MOSTLY VFR CONDITIONS THROUGH THE AFTERNOON WITH SOME CLEARING INTO
THE LATE AFTERNOON. OFFSHORE FLOW WILL HELP KEEP KCEC MOSTLY CLEAR
TONIGHT WITH ONLY A SLIGHT POSSIBILITY OF SOME MVFR CEILINGS POKING
AROUND THE AIRPORT. KACV AND THE HUMBOLDT BAY AREA WILL MORE LIKELY
EXPERIENCE DETERIORATING CONDITIONS LATE TONIGHT WITH MODELS
DEPICTING HIGH RELATIVE HUMIDITY VALUES TO LINGER OVERNIGHT.
OTHERWISE VFR SHOULD PREVAIL FOR INTERIOR AREAS WITH MID-MORNING
CLEARING AT COASTAL AIRFIELDS THURSDAY MORNING. KML


&&

.MARINE...NORTHERLY WINDS WILL GRADUALLY INCREASE OVER THE NEXT FEW
DAYS AS SURFACE HIGH PRESSURE OFFSHORE PINCHES THE PRESSURE GRADIENT
AGAINST THE COASTAL THERMAL TROUGH. SMALL CRAFT CONDITIONS WILL
BEGIN TO DEVELOP ACROSS THE WATERS TONIGHT WITH NEAR GALE FORCE WIND
GUSTS DEVELOPING BY THURSDAY AFTERNOON. THE ADVISORY FOR THE
SOUTHERN WATERS WAS POSTPONED TO BEGIN AT 9 PM TONIGHT AS THE ASCAT
PASS THIS AFTERNOON SHOWED WINDS WERE A LITTLE SLOWER TO INCREASE
THAN PREVIOUSLY FORECAST. THE PRESSURE GRADIENT WILL FLEX AND RELAX
THROUGH THE WEEKEND (CAUSING WINDS TO INCREASE AND THEN DECREASE) AS
AN UPPER LEVEL TROUGH ROTATES SPOKES OF VORTICITY ACROSS THE REGION.
WIDESPREAD WINDS SHOULD FALL BELOW ADVISORY CRITERIA LEVELS BY THE
MIDDLE OF NEXT WEEK AS THE RIDGE OFFSHORE WEAKENS AND SHIFTS
NORTHWARD ALLOWING THE GRADIENT TO RELAX.

SHORTER PERIOD WAVES WILL DEVELOP FIRST ACROSS THE SOUTHERN WATERS
THIS EVENING AND THEN THE NORTHERN WATERS BY LATER TONIGHT. THESE
WAVES WILL RESPOND TO THE INCREASING/DECREASING WINDS THROUGH THE
WEEKEND AND THEN SUBSIDE BY THE MIDDLE OF NEXT WEEK. A MIDDLE PERIOD
SOUTHERLY SWELL WILL CONTINUE TO PROPAGATE THE COASTAL WATERS
THROUGH THE WEEKEND BUT SHALL REMAIN SMALL AND MOSTLY SOUTH OF CAPE
MENDOCINO. THE FORERUNNERS TO A LONG PERIOD SWELL BORN IN THE
SOUTHERN HEMISPHERE WILL IMPACT THE WATERS LATE FRIDAY AND BUILD TO
AROUND 2 FT AT 17 SECONDS ON SUNDAY. LITTLE IMPACTS ARE EXPECTED FOR
MARINERS IN DEEP WATER, HOWEVER, INDIVIDUALS NEARSHORE OR IN THE
SURF ZONE COULD SEE STRONGER CURRENTS ESPECIALLY SOUTH OF CAPE
MENDOCINO. KML


&&

.FIRE WEATHER...LOW-LEVEL MOISTURE HAS AIDED IN RH RECOVERIES
TODAY. OVERNIGHT MOISTURE LEVELS WILL GRADUALLY INCREASE THURSDAY
NIGHT THROUGH THIS WEEKEND. AN UPPER LEVEL TROUGH AND NEARLY CUT
OFF LOW MAY INCREASE INSTABILITY ENOUGH FOR A FEW ISOLATED
THUNDERSTORMS FRIDAY AFTERNOON AND EARLY EVENING OVER TRINITY
COUNTY AND POSSIBLY THE YOLLA BOLLYS. A WEAK OFFSHORE FLOW WILL
DEVELOP EARLY NEXT WEEK RESULTING IN DRIER AIR AND WARMER
TEMPERATURES.


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
     SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 9 AM PDT FRIDAY
     FOR PZZ450.

     SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 9 AM PDT FRIDAY
     FOR PZZ470.

     SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 9 AM PDT FRIDAY
     FOR PZZ455.

     SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 3 AM PDT MONDAY
     FOR PZZ475.

&&

$$

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