Area Forecast Discussion
Issued by NWS Eureka, CA

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FXUS66 KEKA 292229
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
329 PM PDT FRI MAY 29 2015

.SYNOPSIS...WARM AND DRY WEATHER WILL CONTINUE ACROSS THE
INTERIOR THROUGH SATURDAY AS A HIGH PRESSURE RIDGE PERSISTS ACROSS
THE AREA. A WEAK COLD FRONT WILL APPROACH THE AREA SUNDAY AND
MONDAY PRODUCING COOLER TEMPERATURES INLAND AND SOME LIGHT
SHOWERS. LATE IN THE WEEK HIGH PRESSURE WILL RETURN.


&&

.DISCUSSION...AN UPPER LEVEL RIDGE WILL REMAIN OVER NORTHWEST
CALIFORNIA THROUGH SATURDAY LEAVING COASTAL AREAS IN THE STRATUS AND
INTERIOR AREAS WARM AND DRY. HOWEVER SOME BRIEF CLEARING WILL BE
POSSIBLE DURING THE LATE AFTERNOON AND EARLY EVENING HOURS ALONG THE
COAST BEFORE CLOUDS MOVE BACK IN EACH EVENING. THE STRATUS SHOULD
NOT PUSH AS FAR INLAND TONIGHT WITH THE RIDGE DIRECTLY OVER THE WEST
COAST...THUS LOW CLOUDS HAVE BEEN REMOVED FROM THE FORECAST FOR
SOUTHERN MENDOCINO COUNTY. DRIZZLE WILL BE POSSIBLE ON THE COAST
TONIGHT AND IN THE MORNING HOURS ON SATURDAY.

AN UPPER LEVEL LOW THAT HAS BEEN MEANDERING OVER THE PACIFIC OCEAN
WILL MOVE TOWARD NORTHWEST CALIFORNIA ON SUNDAY. MODELS HAVE TRENDED
TOWARD A SLOWER PROGRESSION OF THIS LOW RESULTING IN A DRIER
FORECAST FOR SUNDAY. DECREASED RAIN CHANCES TO SLIGHT FOR THE EARLY
AFTERNOON AND CHANCE IN THE EVENING FOLLOWED BY A RAPID INCREASE FOR
SUNDAY NIGHT THROUGH MONDAY. INSTABILITY WILL BE MARGINAL AS THE LOW
MOVES THROUGH THE REGION EVEN THOUGH THE FIRST SHORTWAVE ON THE
EASTERN SIDE OF THE LOW SUNDAY EVENING WILL TAKE ON A NEGATIVE
TILT...USUALLY CONDUCIVE FOR THUNDERSTORMS. HAVE OPTED TO KEEP THE
SLIGHT CHANCE SUNDAY AFTERNOON AND EVENING OVER THE INTERIOR
MOUNTAINS BUT CONFIDENCE IN STORM DEVELOPMENT IS VERY LOW.

THE LOW WILL MOVE NORTHEAST INTO SOUTHERN OREGON SUNDAY NIGHT INTO
MONDAY MORNING LEAVING NORTHWEST CALIFORNIA IN WESTERLY FLOW WITH
THE GENERAL PATTERN RAPIDLY TRANSITIONING TO ZONAL BEHIND THE LOW
PASSAGE. A SECONDARY SHORTWAVE WILL MOVE THROUGH NORTHWEST
CALIFORNIA DURING THE DAY MONDAY LIKELY TRIGGERING MORE SHOWER
ACTIVITY AND POSSIBLY A STRAY THUNDERSTORM. ONCE AGAIN...INSTABILITY
WILL BE MINIMAL SO ANY STORM ACTIVITY WILL BE OF THE WEAK VARIETY.

TOTAL RAINFALL SUNDAY AFTERNOON THROUGH MONDAY WILL GENERALLY BE
LESS THAN A QUARTER INCH WITH SOME LOCALIZED AREAS RECEIVING UP TO A
HALF INCH. MENDOCINO COUNTY HAS A HIGH CHANCE OF ONLY SEEING A FEW
HUNDREDTHS WHILE THE GREATEST RAINFALL WILL LIKELY BE IN THE
MOUNTAINS OF DEL NORTE COUNTY.

ZONAL FLOW IS PREDICTED IN BOTH THE GFS AND ECMWF TUESDAY AND
WEDNESDAY LEAVING NORTHWEST CALIFORNIA WITH TYPICAL TEMPERATURES FOR
THIS TIME OF YEAR AND DRY CONDITIONS. COASTAL AREAS WILL LIKELY SEE
SOME MORE SUNSHINE THAN IN RECENT DAYS WITH NORTHERLY WINDS
INCREASING OFF THE COAST. BEYOND WEDNESDAY MODELS BEGIN TO DIVERGE
WITH ANOTHER UPPER LEVEL LOW POSSIBLY CUTTING OFF OVER THE WEST
COAST. DEPENDING ON ITS TRACK A RETURN TO AFTERNOON SHOWERS AND
THUNDERSTORMS COULD BE IN STORE FOR LATE NEXT WEEK AND/OR NEXT WEEKEND.
/RPA


&&

.AVIATION...MVFR CONDITIONS AND LIGHT WINDS WILL CONTINUE AT KCEC
AND KACV THIS AFTERNOON DUE TO REDUCED CEILINGS. CLOUDINESS AND
PATCHY FOG WILL INCREASE THIS EVENING AND OVERNIGHT AT KCEC AND KACV
REDUCING CEILINGS AND VISIBILITIES TO IFR CONDITIONS. THE WINDS WILL
BECOME CALM AT TIMES OVERNIGHT AT KCEC AND KACV. VFR CONDITIONS AND
LIGHT WINDS TO CALM CONDITIONS WILL CONTINUE AT KUKI THROUGH
SATURDAY.


&&

.MARINE...NORTHERLY WINDS AND THE SEAS WILL GRADUALLY DIMINISH TODAY
THROUGH THIS WEEKEND AS AN OFFSHORE HIGH PRESSURE SYSTEM WEAKENS. A
WEAK COLD FRONT WILL APPROACH THE AREA SATURDAY EVENING AND SUNDAY
MAINTAINING A WEAK PRESSURE GRADIENT, LIGHT TO MODERATE WINDS AND
LOW SEAS ACROSS THE WATERS THROUGH EARLY NEXT WEEK. THE WINDS AND
SEAS WILL INCREASE TUESDAY ACROSS THE SOUTHERN WATERS THEN WEDNESDAY
ACROSS THE NORTHERN WATERS AS AN OFFSHORE HIGH PRESSURE SYSTEM
STRENGTHENS INCREASING THE PRESSURE GRADIENT ACROSS THE WATERS.


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
     SMALL CRAFT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR PZZ475.

&&

$$

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