Area Forecast Discussion
Issued by NWS Eureka, CA

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000
FXUS66 KEKA 290931
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
231 AM PDT FRI AUG 29 2014

.SYNOPSIS...AN UPPER TROUGH APPROACHING FROM THE NW WILL
BRING A COOLING TREND TO THE AREA THROUGH SATURDAY. ANOTHER
WARMING TREND WILL OCCUR DURING THE FIRST HALF OF NEXT WEEK.
OVERNIGHT AND AT LEAST MORNING CLOUDS WILL CONTINUE TO IMPACT
COASTAL LOCATIONS INTO NEXT WEEK.


&&

.DISCUSSION...AN UPPER LEVEL RIDGE OVER THE WEST COAST IS BEGINNING
TO BE PUSHED EAST AS AN UPPER LEVEL TROUGH DIVES INTO THE PACIFIC
NORTHWEST. THIS TROUGH HAS ENTRAINED UPPER LEVEL MOISTURE FROM THE
REMNANTS OF TROPICAL SYSTEM MARIE WHICH WILL BRING HIGH CLOUDS TO
THE REGION TODAY. MODEL SOUNDINGS INDICATE THAT A STABLE LAYER
SHOULD REMAIN IN PLACE TODAY RESTRICTING ANY CONVECTIVE POTENTIAL.
HOWEVER SOME FAIR WEATHER CUMULUS CLOUDS ARE EXPECTED OVER EASTERN
PORTIONS OF TRINITY AND POSSIBLY MENDOCINO COUNTIES THIS AFTERNOON.
STRATUS ALONG THE COAST WILL LIKELY BE PERSISTENT ONCE AGAIN TODAY
WITH RIDGING STILL IN PLACE.

THE TROUGH MOVING OVER THE REGION TONIGHT INTO SATURDAY WILL LIKELY
DEEPEN THE MARINE LAYER AND ALLOW THE COASTAL CLOUDS TO PENETRATE
FARTHER INLAND. HAVE EXPANDED OVERNIGHT AND MORNING CLOUD COVER INTO
MOST OF THE INTERIOR VALLEYS OF HUMBOLDT...DEL NORTE...AND WESTERN
MENDOCINO COUNTIES. SOME HIGH CLOUDS WILL LINGER OVER THE AREA ON
SATURDAY BUT GENERALLY CLEAR CONDITIONS ARE EXPECTED ACROSS THE
INTERIOR WITH VALLEY CLOUDS MIXING OUT IN THE EARLY TO MID-MORNING.
ONCE AGAIN CLOUDS MAY PERSIST INTO THE AFTERNOON HOURS ALONG THE
IMMEDIATE COAST...BUT WITH THE DEEPER MARINE LAYER MIXING HAS THE
POTENTIAL TO BRING AT LEAST PARTIAL CLEARING LATE IN THE AFTERNOON.

A REPEAT OF SATURDAY NIGHT IS EXPECTED SUNDAY NIGHT AS THE TROUGH
BEGINS TO MOVE SLIGHTLY EAST AND RIDGING BUILDS OVER THE EASTERN
PACIFIC. THE MARINE LAYER WILL ONCE AGAIN BEGIN TO COMPACT AS THE
MARINE INVERSION STRENGTHENS WITH THE BUILDING RIDGE. THUS OVERNIGHT
AND MORNING CLOUDS WILL NOT MOVE AS FAR INLAND BEGINNING SUNDAY
NIGHT INTO EARLY NEXT WEEK.

TEMPERATURES FRIDAY INTO THE WEEKEND WILL BE SEVERAL DEGREES COOLER
THAN THE LAST FEW DAYS ACROSS THE INTERIOR WITH HIGHER OVERNIGHT RH
RECOVERIES EXPECTED. AS THE RIDGE RE-ESTABLISHES ITSELF OVER THE
EASTERN PACIFIC AND NOSES OVER THE WEST COAST...TEMPERATURES WILL
REBOUND INTO NEXT WEEK. TEMPERATURES NEAR THE IMMEDIATE COAST WILL
BE FAIRLY CONSISTENT THROUGH THE FORECAST PERIOD BUT WITH BETTER
CLEARING POTENTIAL SATURDAY AND SUNDAY AFTERNOONS...HIGHS MAY JUMP A
FEW DEGREES INTO THE MID-60S.

MODELS CONTINUE TO INDICATE ANOTHER TROUGH PUSHING DOWN THE WEST
COAST MID TO LATE NEXT WEEK. THE TROUGH IS CURRENTLY FORECAST TO
REMAIN DRY...BUT WITH COOLER AIR ALOFT ATMOSPHERIC PROFILES MAY
BECOME MORE CONDUCIVE TO CONVECTIVE DEVELOPMENT LATE IN THE WEEK.
HAVE OPTED TO INCLUDE CLIMATOLOGICALLY NORMAL CHANCES FOR
PRECIPITATION NEXT FRIDAY...BUT THIS IS STILL LESS THAN 10
PERCENT. RPA


&&

.AVIATION...LIFR TO IFR CONDITIONS AND LIGHT WINDS TO CALM CONDITIONS
WILL CONTINUE AT KCEC AND KACV THROUGH THE EARLY MORNING. THE LOWER
CONDITIONS ARE DUE TO REDUCED CEILINGS AND VISIBILITIES DUE TO PATCHY FOG
AND STRATUS OCCURRING ACROSS SOME COASTAL AREAS. IFR TO MVFR CONDITIONS
WILL PREVAIL AT KCEC AND KACV THIS AFTERNOON. THE LOWER CONDITIONS WILL
OCCUR DUE TO LOWER CEILINGS. LIGHT TO MODERATE WINDS WILL OCCUR AT KCEC
AND KACV THIS AFTERNOON. VFR CONDITIONS AND LIGHT WINDS TO CALM CONDITIONS
WILL CONTINUE AT KUKI THE NEXT FEW DAYS.


&&

.MARINE...AN OFFSHORE HIGH PRESSURE RIDGE WILL STRENGTHEN THE NEXT
FEW DAYS. THE HIGH PRESSURE RIDGE COMBINED WITH AN INLAND THERMAL LOW
PRESSURE TROUGH WILL INCREASE THE PRESSURE GRADIENT ACROSS THE WATERS
THE NEXT FEW DAYS. THE PRESSURE GRADIENT WILL TIGHTEN MORE ACROSS THE
OUTER WATERS.  THEREFORE THE WINDS AND SEAS WILL GRADUALLY INCREASE
THE NEXT FEW DAYS PRIMARILY ACROSS THE SOUTHERN OUTER WATERS. A SMALL
CRAFT ADVISORY IS IN EFFECT ACROSS THE SOUTHERN OUTER WATERS THE NEXT
FEW DAYS AND WILL LIKELY BE EXTENDED. THERE WILL BE AN INCREASE IN
THE WINDS AND SEAS ACROSS ALL THE WATERS THIS WEEKEND AND EARLY NEXT
WEEK AS THE HIGH PRESSURE SYSTEM OFFSHORE STRENGTHENS TIGHTENING THE
PRESSURE GRADIENT. SMALL CRAFT ADVISORIES ARE LIKELY ACROSS ALL THE
WATERS THIS WEEKEND AND EARLY NEXT WEEK.


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
     SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 10 AM PDT
     SATURDAY PZZ470.

     SMALL CRAFT ADVISORY UNTIL 10 AM PDT SATURDAY PZZ475.

&&

$$

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