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000
FXUS66 KEKA 182101
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
240 PM PDT TUE JUN 18 2013

.SYNOPSIS...AN UPPER TROUGH OFFSHORE THE PACIFIC NORTHWEST WILL
BRING COOLING TO THE INTERIOR AND CHANCE OF LIGHT SHOWERS NORTH OF
CAPE MENDOCINO THROUGH MID-WEEK. WARMER INLAND TEMPERATURES WILL
RETURN LATE IN THE WEEK.

&&

.SHORT TERM...LARGE UPPER LOW CONTINUES TO PINWHEEL OFF THE OR AND
WA COASTS WITH INSTABILITY NOTED IN THE MOSTLY OPEN CELLULAR CU
FIELD THIS AFTERNOON. SHORTWAVE ENERGY WRAPPING AROUND THE UPPER LOW
SHOULD GRADUALLY PROMOTE SHOWER ACTIVITY OVER FAVORABLE UPSLOPE
TERRAIN.  AS OF 2 PM LIGHT SHOWERS WERE DETECTED OVER THE COASTAL
MOUNTAINS OF DEL NORTE COUNTY. BOTH THE NAM AND GFS MODELS CONTINUE
TO INDICATE ENUF WEAK INSTABILITY TO CONTINUE THE INCLUSION OF ISOLD
TSTMS FOR PORTIONS OF THE NORTH COAST INTERIOR AND UPPER TRINITY
RIVER ZONES LATE THIS AFTERNOON AND EARLY THIS EVENING...HOWEVER AS
OF RIGHT NOW CUMULUS DEVELOPMENT REMAINS SHALLOW OVER THOSE AREAS.
DUE TO THE COLDER AIR ASSOCIATED WITH THE LOW...MAX TEMPERATURES
OVER THE INTERIOR WILL AVERAGE ABOUT 10 DEGREES BELOW NORMAL TODAY
AND WED. SNOW FLURRIES ARE POSSIBLE IN THE HIGHEST ELEVATIONS OF THE
TRINITY ALPS EARLY WED MORNING. PRECIP ACROSS THE N ZONES WILL
GRADUALLY COME TO AN END BY WED NIGHT. STORM TOTAL PRECIP ACROSS THE
HIGHER TERRAIN OF DEL NORTE COUNTY MAY APPROACH 1/4 INCH...BUT MOST
LOCALES WILL SEE LESS PRECIP. MODELS HAVE BEEN TRENDING DRIER WITH
THIS SYSTEM...SO FORECAST QPF VALUES MAY STILL BE A BIT HIGH.

.LONG TERM...UPPER LOW WILL CONTINUE TO MOVE NE AND FILL THRU THE
REMAINDER OF THE WEEK. A WEAK RIDGE OF HIGH PRESSURE WILL BRIEFLY
BUILD OVER THE REGION ACCOMPANIED BY INLAND TEMPERATURES RETURNING
TO NEAR OR SLIGHTLY ABOVE NORMAL BY FRI AND CONTINUING INTO EARLY
NEXT WEEK. HAVE GONE SLIGHTLY ABOVE CLIMO POPS OVER OUR N ZONES
EARLY NEXT WEEK AS AN UPPER TROF BECOMES BETTER DEFINED OVER THE W
COAST. JT/SEC

&&

.AVIATION...A WEAK PRESSURE GRADIENT OVER NORTHWEST CALIFORNIA WILL
BRING LIGHT AND TERRAIN DRIVEN WINDS TO THE TAF SITES. COASTAL
AIRSTRIPS ARE VFR, BUT SOME COASTAL STRATUS MAY FORM THIS EVENING
AND TONIGHT, BRINGING REDUCED CEILINGS. THOUGH, UNCERTAINTY IS HIGH.

&&

.MARINE...THIS MORNINGS ASCAT PASS SHOWED LIGHT WINDS ACROSS THE
WATERS. NEARSHORE BUOYS ALSO SHOW LIGHT WINDS AND SEAS AROUND 3 FT.
A WEAK PRESSURE GRADIENT WILL CONTINUE TO BRING LIGHT WINDS AND LOW
SEAS TO THE WATERS THROUGH WEDNESDAY. MODELS ARE IN GOOD AGREEMENT
SHOWING THE PRESSURE GRADIENT TIGHTENING THURSDAY INTO THE WEEKEND,
BRINGING INCREASED NORTHERLY WINDS AND BUILDING SHORT PERIOD WAVES.

&&

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

&&

$$

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