Area Forecast Discussion
Issued by NWS Eureka, CA

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855
FXUS66 KEKA 072202
AFDEKA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
202 PM PST SUN FEB 7 2016

.SYNOPSIS...HIGH PRESSURE WILL BRING MOSTLY DRY WEATHER AND
ABOVE NORMAL TEMPERATURES TO NORTHWEST CALIFORNIA OVER THE NEXT
SEVERAL DAYS. A WEAK FRONT WILL BRING THE NEXT CHANCE FOR LIGHT
RAIN LATE NEXT WEEK.


&&

.DISCUSSION...A HIGHLY AMPLIFIED RIDGE WILL REMAIN OVER THE
REGION FOR THE NEXT COUPLE OF DAYS RESULTING IN MOSTLY SUNNY
CONDITIONS AND WARM TEMPERATURES. A THERMAL TROUGH HAS SHIFTED
OFF THE COAST ALLOWING OFFSHORE FLOW TO COMMENCE SEVERAL HUNDRED FEET
ABOVE SEA LEVEL. THE ATMOSPHERIC PROFILER AT THE AIRPORT IN
MCKINLEYVILLE IS INDICATING THAT WINDS HAVE NOW TURNED OUT OF THE
EAST ALOFT. THE DOWNSLOPE FLOW WILL POTENTIALLY RESULT IN A
RATHER WARM NIGHT TONIGHT AT COASTAL SITES WITH LOWS IN THE UPPER
40S. INTERIOR AREAS WILL AGAIN SEE SOME PATCHY VALLEY FOG AND
TEMPERATURES FALLING INTO THE MID TO LOWER 40S AND EVEN A FEW
UPPER 30S FOR SOME OF THE NORMALLY COLDER SPOTS.

THE OFFSHORE FLOW WILL PERSIST MONDAY AND TUESDAY...BECOMING MORE
SOUTHEAST ON MONDAY. TEMPERATURES OVER THE ENTIRE REGION WILL
RANGE FROM THE 60S TO MID 70S...HIGHEST IN SOUTHERN-INTERIOR
MENDOCINO COUNTY. WE ARE CURRENTLY FORECASTING HIGH TEMPERATURES
TO PEAK A COUPLE DEGREES BELOW RECORDS AT THE THREE CLIMATE SITES
(EUREKA-CRESCENT CITY-UKIAH) MONDAY AFTERNOON AND POTENTIALLY
AGAIN TUESDAY AFTERNOON...BUT THESE RECORDS COULD BE REACHED
DEPENDING ON THE EXACT WIND DIRECTION. 850 AND 1000 MB
TEMPERATURES ARE 2 TO 4 STANDARD DEVIATIONS ABOVE THE NORM FOR
THIS TIME OF YEAR...SO THERE IS VERY HIGH CONFIDENCE IN THE WARM
SURFACE TEMPERATURES. IN FACT...THE RETURN INTERVAL FOR A RIDGE OF
THIS MAGNITUDE OVER THE WEST COAST AT THIS TIME OF YEAR IS LESS
THAN ONCE EVERY 30 YEARS PER NAEFS MODEL ANALYSIS.

THE RIDGE IS NOT FORECAST TO FULLY BREAK DOWN FOR THE FORESEEABLE
FUTURE...HOWEVER BOTH THE GFS AND ECMWF INDICATE A WEAKENING TROUGH
COULD BRING SOME LIGHT RAIN TOWARD THE REGION LATE WEEK. THIS WILL
BEGIN AS AN INCREASE IN CLOUD COVER BEGINNING TUESDAY INTO WEDNESDAY
WITH THE POTENTIAL FOR A FEW SPRINKLES OVER THE NORTHERN PORTION OF
THE AREA WEDNESDAY NIGHT OR THURSDAY. BUT IN GENERAL MOST AREAS WILL
REMAIN DRY UNTIL THURSDAY NIGHT OR FRIDAY WHEN THE BEST CHANCE FOR
RAIN IS EXPECTED TO ARRIVE WITH THE QUICK PASSAGE OF A COLD FRONT.
CONSIDERING THE LAST STORM WEAKENED SIGNIFICANTLY AS IT APPROACHED
THE COAST WITH THE BUILDING RIDGE LAST FRIDAY NIGHT...THERE IS
POTENTIAL THAT THE MODELS ARE PRODUCING TOO MUCH PRECIPITATION FOR
THE LATE WEEK SYSTEM. SLIGHT CHANCE TO CHANCE POSSIBILITIES FOR
RAIN HAVE BEEN MAINTAINED THURSDAY THROUGH SATURDAY FOR MOST AREAS
EXCEPT DEL NORTE COUNTY WHERE CONFIDENCE IS A LITTLE HIGHER THAT
AT LEAST SOME PRECIPITATION IS LIKELY ON FRIDAY.


&&

.AVIATION...VFR CONDITIONS AND LIGHT WINDS TO CALM CONDITIONS
WILL CONTINUE AT KCEC, KACV AND KUKI THROUGH TONIGHT. VFR CONDITIONS
WILL PREVAIL AT KCEC, KACV AND KUKI MONDAY AS A HIGH PRESSURE RIDGE
PERSIST ACROSS THE REGION.


&&

.MARINE...LIGHT TO MODERATE WINDS WILL CONTINUE ACROSS THE WATERS
THROUGH THE END OF THIS WEEK. A WESTERLY SWELL GENERATED BY A
STRONG LOW PRESSURE SYSTEM SOUTH OF THE ALEUTIAN ISLANDS WILL BRIEFLY
INCREASE LONG PERIOD SEAS ACROSS THE WATERS ON MONDAY. SEAS WILL
SUBSIDE TUESDAY AND WEDNESDAY THEN BUILD AGAIN ON THURSDAY. SMALL
CRAFT ADVISORIES ARE LIKELY ACROSS ALL THE WATERS THURSDAY AND FRIDAY
DUE TO ELEVATED SEAS.


&&

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

$$

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