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000
FXUS66 KEKA 102250
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
350 PM PDT MON MAR 10 2014

.SYNOPSIS...BUILDING HIGH PRESSURE WILL DOMINATE THE WEATHER
PATTERN FOR NWCA THROUGH THE WEEKEND. DRY WEATHER WITH WARMING
TEMPERATURES WILL TAKE PLACE...WITH SOME FROSTY NIGHTS ACROSS
INTERIOR VALLEYS.


&&

.DISCUSSION...ISOLATED SHOWERS DISSIPATED BY LATE MORNING AS THE
SHORTWAVE TROUGH SLID ACROSS NORTHERN CA ALLOWING CLOUD COVER TO
SLOWLY CLEAR THROUGHOUT THE AFTERNOON. VISIBLE SATELLITE IMAGERY
SHOWS REMAINING ALTOCU ACROSS HIGHER TERRAIN ALONG WITH FEW CLOUDS
OFFSHORE AS OF 22Z. MOSTLY CLEAR CONDITIONS WILL LAST INTO THE
EVENING AS A BUILDING RIDGE INTRODUCES A DRIER AIRMASS ACROSS
NWCA. HOWEVER, INCREASING STABILITY AND RESIDUAL MOISTURE WILL
ALLOW FOR THE FORMATION OF SOME PATCHY FOG ACROSS INTERIOR VALLEYS
IN EASTERN HUMBOLDT AND TRINITY COUNTIES TONIGHT AND TUESDAY
NIGHT. OTHERWISE NWCA SHALL REMAIN RELATIVELY CLEAR OVER THE NEXT
FEW DAYS.

CLEAR SKIES AND DECREASING RELATIVE HUMIDITY WILL PROMOTE
RADIATIONAL COOLING AT THE SURFACE WHICH WILL RESULT IN FROSTY
CONDITIONS TONIGHT AND TUESDAY NIGHT. A FROST ADVISORY WILL REMAIN IN
EFFECT FOR VALLEYS ACROSS INTERIOR MENDOCINO LATE TONIGHT. IT IS
POSSIBLE FOR A FEW VALLEYS OF EASTERN HUMBOLDT AND DEL NORTE
COUNTIES TO SEE SOME TEMPERATURES IN THE LOW TO MID 30S HOWEVER
CONFIDENCE IS LOWER SINCE MANY OF THESE VALLEYS WILL HAVE PATCHY
FOG. MOS GUIDANCE IS TRENDING TOWARDS AN EVEN COOLER NIGHT ON
TUESDAY SO WE ANTICIPATE ANOTHER ADVISORY FOR INTERIOR MENDOCINO
ON TUESDAY NIGHT AND QUITE POSSIBLY FOR INTERIOR HUMBOLDT/DEL
NORTE.

THE WARM/DRY TREND WILL CONTINUE INTO THE WEEKEND AS BUILDING HIGH
PRESSURE DOMINATES THE WEATHER PATTERN. EXPECT SUNSHINE AND
INCREASINGLY WARM TEMPERATURES WITH SOME AREAS POSSIBLY REACHING
THE LOW 80S ACROSS THE INTERIOR VALLEYS THIS WEEKEND. KML

&&

.AVIATION...UPPER LEVEL RIDGING WILL CONTINUE TO BUILD OVER THE WEST
COAST REDUCING SHOWER ACTIVITY AND RESULTING IN CLEARING SKIES THIS
AFTERNOON. SOME INTERIOR VALLEY FOG IS EXPECTED TO DEVELOP OVERNIGHT
WITH PLENTY OF LOW LEVEL MOISTURE EXPECTED TO POOL IN VALLEY AREAS.
OTHERWISE CONDITIONS SHOULD REMAIN VFR. RPA


&&

.MARINE...NORTHERLY WINDS ARE INCREASING TODAY AS A COASTAL TROUGH
DEVELOPS AND HIGH PRESSURE STRENGTHENS OVER THE EASTERN PACIFIC.
SMALL CRAFT WINDS AND SEAS ARE EXPECTED IN THE SOUTHERN WATERS
TONIGHT AND THEN WILL EXPAND NORTH INTO THE NORTHERN OUTER WATERS ON
TUESDAY. GUSTS HAVE BEEN PERSISTENT NEAR 25 KT AT BUOY 14 TODAY AND
SHOULD PERSIST THROUGH TONIGHT. THUS A SMALL CRAFT ADVISORY HAS BEEN
ISSUED FOR THE SOUTHERN PORTION OF THE SOUTHERN INNER WATERS EVEN
THOUGH MUCH OF THE NORTHERN PORTION OF THE ZONE WILL REMAIN BELOW
SMALL CRAFT CONDITIONS. SEAS MAY BUILD TO NEAR HAZARDOUS SEAS
CRITERIA IN THE WESTERN HALF OF THE NORTHERN OUTER WATERS ON TUESDAY
INTO TUESDAY EVENING. CONSIDERING THIS IS NOT HIGHLY CERTAIN AND THE
HAZARDOUS SEAS CRITERIA SEAS MIGHT REMAIN CONFINED TO THE NORTHWEST
CORNER...HAVE OPTED TO STICK WITH ONLY A SMALL CRAFT ADVISORY FOR
THE NORTHER OUTER WATERS.

OFFSHORE FLOW WILL DEVELOP TUESDAY NIGHT INTO WEDNESDAY AS A
SHORTWAVE TROUGH PUSHES INTO THE PACIFIC NORTHWEST SQUASHING THE
RIDGE OVER THE WEST COAST. WINDS AND SHORT PERIOD SEAS WILL SUBSIDE
FOR A 24 HOUR PERIOD BEFORE HIGH PRESSURE RE-ESTABLISHES ITSELF OVER
THE EASTERN PACIFIC AND NORTHERLY WINDS STRENGTHEN AGAIN ON
THURSDAY. THERE IS POTENTIAL FOR ANOTHER WEAK UPPER LEVEL WAVE TO
MOVE INTO THE PACIFIC NORTHWEST FRIDAY INTO SATURDAY WHICH MAY ALLOW
WINDS TO BECOME LIGHT AND POSSIBLY TURN OUT OF THE SOUTH. HOWEVER
WITH MODELS STILL HAVING DIFFICULTY PREDICTING THE MID TO LONG TERM
FORECAST...KEPT LIGHT NORTHERLIES IN THE FORECAST.

A LARGE LONG PERIOD SWELL WILL BUILD INTO THE WATERS TUESDAY NIGHT
INTO WEDNESDAY BRINGING A POTENTIAL FOR SNEAKER WAVES ALONG THE
COAST. WITH THE OFFSHORE FLOW DEVELOPING RESULTING IN NICE WEATHER
AND THE SWELL BEGINNING AROUND 20 SECONDS...CONFIDENCE IS INCREASING
THAT SNEAKER WAVES WILL BE A CONCERN AND A WEATHER STORY HAS BEEN
ISSUED TO COVER THE THREAT. RPA


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...FROST ADVISORY FROM 1 AM TO 9 AM PDT TUESDAY CAZ076.

NORTHWEST CALIFORNIA COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 3 AM PDT TUESDAY PZZ455.

     SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 5 AM PDT WEDNESDAY
     PZZ470.

     SMALL CRAFT ADVISORY UNTIL 5 AM PDT WEDNESDAY PZZ475.

&&

$$

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