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000
FXUS66 KEKA 182158
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
258 PM PDT SAT MAY 18 2013

.SYNOPSIS...HIGH PRESSURE OVER THE REGION SHOULD ALLOW WARMER
TEMPERATURES AND DRIER CONDITIONS TO PERSIST THROUGH MONDAY. AN
UPPER LEVEL DISTURBANCE APPROACHING FROM THE NORTH WILL BRING THE
THREAT OF SHOWERS NORTH OF CAPE MENDOCINO TUESDAY THROUGH THE END
OF NEXT WEEK.

&&

.DISCUSSION...MINOR CHANGES MADE TO THE FORECAST. A WEAK
DISTURBANCE IS CURRENTLY MOVING INLAND AND HIGH PRESSURE IS
BUILDING OVER THE REGION. SATELLITE SHOWS CLOUDS ALONG THE REDWOOD
COAST, MOVING TO THE EAST, WHILE RADAR SHOWS NO PRECIPITATION.
SKIES SHOULD CLEAR TONIGHT, ALLOWING FOR SOME FOG TO FORM AROUND
HUMBOLDT BAY AND THE EEL RIVER VALLEY. THIS SHOULD QUICKLY BURN
OFF ON SUNDAY. EXPECT DRY WEATHER AND WARMER TEMPERATURES SUNDAY
AND MONDAY DUE TO HIGH PRESSURE OVER THE AREA. THE RIDGE STARTS TO
BREAK DOWN EARLY NEXT WEEK AND IS REPLACED BY A TROUGH BUILDING IN
FROM THE PACIFIC NORTHWEST. THE MAIN ENERGY WITH THIS SHOULD STAY
TO OUR NORTH FROM ROUGHLY TUESDAY THROUGH THE END OF NEXT WEEK.
INSTABILITY SHOWERS ARE LOOKING MORE LIKELY, ESPECIALLY NOW THAT
THE MODELS ARE SHOWING SOME PACIFIC MOISTURE WRAPPING INTO THE
TROUGH. RAISED POPS TO ALMOST DOUBLE CLIMO NORTH OF CAPE MENDOCINO
FROM TUESDAY ONWARD, WHEN THE LOW WILL BE CLOSES TO US. KEPT POPS
BELOW CLIMO ACROSS THE SOUTHERN PORTIONS OF OUR AREA, WHERE THERE
WILL BE VERY LITTLE INSTABILITY. THE GREATEST THREAT OF SHOWERS
WILL BE DURING THE DAY AND THE POPS REFLECT THIS. NO THUNDERSTORMS
ARE FORECAST AT THIS TIME.

&&

.AVIATION...A COLD FRONT WILL CONTINUE TO BRING LOW CIGS TO
COASTAL SITES THIS AFTERNOON AND OVERNIGHT BEFORE IT FINALLY MOVES
INLAND LATE TONIGHT. IN THE EARLY MORNING THE DRIER AIR BEHIND THE
FRONT WILL MIX OUT THE LOWER LEVEL CLOUDS AND IMPROVE CONDITIONS
FROM MVFR TO VFR. FARTHER INLAND SOME PATCHY FOG WILL BE POSSIBLE
OVERNIGHT IN THE VALLEYS WITH VFR PERSISTING ELSEWHERE. VALLEY FOG
SHOULD DISSIPATE QUICKLY SUNDAY MORNING. RPA

&&

.MARINE...HIGH PRESSURE WILL BUILD OVER THE EASTERN PACIFIC AS A
COLD FRONT MOVES INLAND TONIGHT. THIS WILL STRENGTHEN THE PRESSURE
GRADIENT OVER THE WATERS WHICH WILL BE FURTHER STRENGTHENED SUNDAY
INTO MONDAY AS THE THERMAL TROUGH STRENGTHENS OVER THE CENTRAL
VALLEY. GUSTS TO 40 KT ARE EXPECTED OVER THE OUTER WATERS WHEN THE
PRESSURE GRADIENT STRENGTHENS WITH SEAS QUICKLY BUILDING TO
BETWEEN 12 AND 15 FEET. THUS THE GALE WARNINGS HAVE BEEN CONTINUED
WITH SMALL CRAFTS FOR THE INNER WATERS. A TROUGH AND SURFACE LOW
WILL PUSH DOWN THE COAST TUESDAY DISTURBING THE PRESSURE GRADIENT
AND WEAKENING THE WINDS. SEAS WILL LIKELY REMAIN ELEVATED...AND
SOME GUSTS TO 25 KT WILL BE POSSIBLE...SO SMALL CRAFT CONDITIONS
WILL LIKELY CONTINUE...BUT GENERALLY A WEAKENING TREND IN THE
WINDS WILL BEGIN AS THIS LOW APPROACHES THE WATERS ON TUESDAY.
NORTHERLY WINDS WILL LIKELY RESTRENGTHEN SOUTH OF THE CAPE
WEDNESDAY AFTER THE LOW PASSES THROUGH THE REGION. WINDS WILL BE
LOWER FARTHER NORTH WHERE INFLUENCES FROM A CUT OFF UPPER LOW OVER
THE PACIFIC NORTHWEST WILL BE GREATER. RPA

&&

.EKA WATCHES/WARNINGS/ADVISORIES...

CA...NONE.

NORTHWEST CALIFORNIA COASTAL WATERS...

GALE WARNING FOR PZZ470-475.
SMALL CRAFT ADVISORY FOR PZZ450-455-470-475.

&&

$$

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