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000
FXUS66 KEKA 161135
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
435 AM PDT SUN JUN 16 2013

.SYNOPSIS...DRY WEATHER WILL CONTINUE THROUGH MONDAY MORNING AS
HIGH PRESSURE REMAINS OVER THE REGION. AN UPPER TROUGH WILL SLOWLY
APPROACH THE WEST COAST EARLY NEXT WEEK AND BRING A CHANCE OF
LIGHT SHOWERS MAINLY NORTH OF CAPE MENDOCINO. THIS TROUGH WILL
ALSO BRING COOLER TEMPERATURES TO THE INTERIOR THROUGH THE MIDDLE
OF NEXT WEEK.

&&

.SHORT TERM...LOW CLOUDS HAVE THICKENED ONCE AGAIN ALONG THE
REDWOOD COAST AND UP THE EEL RIVER VALLEY. LOW CLOUDINESS IS ALSO
EVIDENT ON 11-3.9 MICRON SATELLITE IMAGERY OVER PORTIONS OF
COASTAL MENDOCINO COUNTY AND SOME INTERIOR VALLEYS. WEAK SHORTWAVE
PINWHEELING AROUND UPPER LOW OFF THE PAC NW COAST IS PRESENTLY
PRODUCING A BAND OF MID AND HIGH CLOUDINESS JUST OFF THE NW CA
COAST. THIS SHORTWAVE MAY HELP TO PRODUCE SOME DRIZZLE THIS
MORNING. BUT...AS IT MOVES BY...IT MAY ALSO HELP BREAK UP
CLOUDINESS DURING THE AFTERNOON ALONG THE COAST. CLOUDS WILL ALSO
ERODE THIS MORNING FROM THE E EDGE DUE TO DIURNAL MIXING. MORE
INSTABILITY WILL BE PRESENT OVER THE N CA MOUNTAINS THIS
AFTERNOON...BUT CU DEVELOPMENT IS EXPECTED TO BE MOSTLY NE OF OUR
COUNTY WARNING AREA.

AS UPPER LOW MOVES SLOWLY INLAND OVER WA AND N OR...POPS WILL
INCREASE MON AFTERNOON AND MON NIGHT WITH HIGHEST POPS OVER OUR N
ZONES. BEST CHANCES OF RAIN WILL DURING THE DAY ON TUE WITH
PERHAPS ANOTHER INCREASE LATE TUE NIGHT. HAVE CAPPED POPS AT 50
PERCENT OVER DEL NORTE COUNTY AND STILL EXPECT RAINFALL TOTALS TO
BE LIGHT WITH PERHAPS A QUARTER INCH OVER TERRAIN OF W DEL NORTE.
ENUF S FLOW MAY DEVELOP MON MORNING TO ALLOW SOME DOWNSLOPING
ALONG PORTIONS OF THE REDWOOD COAST. HAVE TWEAKED MAX TEMPERATURES
UP ANOTHER DEGREE OR TWO DURING THIS PERIOD. INTERIOR TEMPERATURES WILL
BE ON THE DECLINE EARLY IN THE COMING WEEK AS UPPER TROF MOVES E
WITH DAYTIME HIGHS SOME 10 DEGREES BELOW NORMAL ON TUE.

.LONG TERM...UPPER LOW WILL CONTINUE TO SHIFT NE AND FILL AS FLOW
ACROSS THE AREA BECOMES MORE ZONAL. AS A RESULT...RAINS WILL
DECREASE LATE IN THE COMING WEEK AND INTERIOR TEMPERATURES WILL
INCREASE ONCE AGAIN. /SEC

&&

.AVIATION...SOMEWHAT TRICKY FORECAST WITH A WEAK SFC PRESSURE
GRADIENT BUT GENERAL UPPER TROUGHING RESULTING IN A WEAK
INVERSION. PERSISTENCE FORECAST WILL PROBABLY BE THE BEST COURSE
OF ACTION IN THIS INSTANCE, SINCE VERY LITTLE HAS CHANGED SINCE
YESTERDAY. WEAKER GRADIENT AND RELATIVELY DEEP MARINE LAYER WILL
TEND TO PROMOTE A MORE STAGNANT BOUNDARY LAYER AND MORE PERSISTENT
CLOUD COVERAGE TODAY ALONG THE NORTH COAST INCLUDING KACV AND
KCEC. HOWEVER THERE STILL WILL BE AREAS OF CLEARING ALLOWED AS THE
INVERSION WILL BE RELATIVELY WEAK. WITH SHORTWAVES MOVING THROUGH
WOULD NOT BE SURPRISED TO SEE SOME DRIZZLE AND TEMPORARY LOWERING
OF CIGS BELOW 1KFT BUT THIS SHOULD NOT LAST PAST 15Z. ANY VSBY
REDUCTION WILL BE BRIEF AND MOSTLY MVFR. WILL KEEP BOTH COASTAL
SITES 1-2KFT CIGS THROUGH TODAY BUT COULD BE A PERIOD OF BKN OR
SCT CIGS THIS AFTERNOON OR EVENING. EXPECT SIMILAR CONDITIONS THE
NEXT NIGHT OR TWO. AAD

&&

.MARINE...MINIMAL CHANGES NEEDED TO THE GOING FORECAST FOR WINDS
AND SEAS. AN UPPER TROUGH WILL SLOWLY APPROACH THE COAST WHILE NOT
ACTUALLY PASSING THROUGH UNTIL WEDNESDAY. THIS WILL KEEP THE
PACIFIC HIGH IN A WEAKENED STATE AND ALLOW A WEAK SFC LOW
REFLECTION TO APPROACH EARLY NEXT WEEK. THIS WILL RESULT IN A
PERIOD OF LIGHT SOUTHWESTERLY WINDS TO THE WATERS NORTH OF CAPE
MENDOCINO BEGINNING AS EARLY AS TONIGHT. OTHERWISE WINDS NORTH OF
THE CAPE WILL REMAIN VERY LIGHT AND VARIABLE TODAY WHILE
NORTHERLIES WILL GUST LOCALLY UP TO 20 KT TO THE LEE OF CAPE
MENDOCINO. SEAS WILL TRANSITION TOWARD MORE OF A WESTERLY WAVE AT
AN 8-10 SECOND PERIOD. NORTHERLIES WILL LIKELY BEGIN PICKING UP
AGAIN THURSDAY. AAD

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...NONE.

&&

$$

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