Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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000
FXUS66 KMTR 290538
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1038 PM PDT THU AUG 28 2014

.SYNOPSIS...NORMAL TO SLIGHTLY ABOVE NORMAL TEMPERATURES AND DRY
WEATHER WILL PERSIST THROUGH THE HOLIDAY WEEKEND.

&&

.DISCUSSION...AS OF 8:27 PM PDT THURSDAY...THE FINAL LOW LIGHT
VISIBLE SATELLITE IMAGE IS SHOWING LOW CLOUDS BANKING AGAINST THE
CENTRAL CALIFORNIA COAST THIS EVENING. LOW CLOUDS ARE CURRENTLY
BEING REPORTED AT WATSONVILLE AIRPORT, MONTEREY, SALINAS AND
HALF MOON BAY AIRPORTS. THE FORT ORD PROFILER SHOWS A SOLID 2000
FOOT DEEP MARINE LAYER AND THE SURFACE PRESSURE GRADIENT IS
LIGHTLY ONSHORE. THEREFORE...EXPECT LOW CLOUDS TO RETURN TO THE
INLAND VALLEYS OVERNIGHT.

THE FINAL LOW LIGHT VISIBLE SATELLITE IMAGE ALSO SHOWS SOME MID TO
UPPER LEVEL CLOUDS ENTERING THE COASTAL WATERS. THESE CLOUDS ARE
ENTRAINED TROPICAL MOISTURE FROM TROPICAL STORM MARIE. THIS
MOISTURE WILL MOVE OVER THE FORECAST AREA TOMORROW BUT SHOULD NOT
RESULT IN ANY RAIN. HOWEVER...THE SKIES WILL BE CLOUDIER TOMORROW
AND IT WILL PROBABLY FEEL MUGGY. THE CURRENT FORECAST PACKAGE
LOOKS GOOD SO NO UP DATES ARE NEEDED THIS EVENING.

PREVIOUS DISCUSSION...AS OF 3:00 PM PDT THURSDAY...AFTER FAIRLY
WIDESPREAD CLOUDINESS ACROSS MOST OF THE URBAN AREAS TODAY, CLOUDS
HAVE CLEARED AND MOST SPOTS ARE SEEING SUNNY SKIES. ONLY EXCEPTION
LOOKS LIKE A FEW PATCHES OF CLOUDS STILL ALONG THE IMMEDIATE
COASTLINE. TEMPERATURES HAVE BEEN RUNNING A FEW DEGREES COOLER
THAN YESTERDAY ALTHOUGH HIGHS SHOULD STILL UP NEAR NORMAL VALUES
-- 60S TO MID 70S AT THE COAST WITH MID 70S TO UPPER 80S INLAND.

SATELLITE NICELY SHOWS TROPICAL STORM MARIE CHURNING AROUND 900
MILES TO THE SOUTHWEST OF SAN FRANCISCO CONTINUING TO TRACK TO THE
NW. NHC FORECAST CALLS FOR IT TO CONTINUE TO DISSIPATE AND BECOME
POST-TROPICAL BY TONIGHT. CLOSER TO HOME, THE BIG QUESTION OF THE
PAST WEEK HAS BEEN IF ANY MOISTURE ASSOCIATED WITH MARIE WOULD
BECOME ENTRAINED IN THE FLOW AND MOVE INTO OUR CWA AS A LONGWAVE
TROF SWEEPS INTO THE PACNW. MODELS HAVE BEEN IN EXCELLENT
AGREEMENT OVER THE PAST THREE DAYS THAT ANY RAINFALL WOULD REMAIN
WELL OUT OF OUR AREA DUE TO A RIDGE BLOCKING ANY ADVANCE.

ALTHOUGH RAIN OR SHOWERS WILL NOT MAKE IT TO THE COAST, HIGH
CLOUDS ALONG WITH HIGHER HUMIDITY READINGS CAN BE EXPECTED FRIDAY
AND SATURDAY. HIGHS ON FRIDAY SHOULD BE CLOSE TO WHAT WE SEE
TODAY. LOCALLY BREEZY CONDITIONS ARE POSSIBLE ESPECIALLY FOR THE
NORTH AND EAST BAY MOUNTAINS BOTH DAYS DUE TO THE PROXIMITY OF THE
LONGWAVE TROF. 925 MB SPEEDS ARE ONLY EXPECTED TO BE 15-25 KT SO
WE SHOULD BE WELL UNDER AND ADVISORY LEVELS.

QUIET WEATHER WITH NEAR NORMAL TEMPERATURES LOOKS LIKELY ALL OF
THE WAY THROUGH THE UPCOMING WEEKEND INTO THE FIRST HALF OF NEXT
WEEK AS THE LONGWAVE TROF DEPARTS WELL TO THE EAST WHILE A RIDGE
OF HIGH PRESSURE STAYS IN CONTROL OUT OVER THE PACIFIC. A DRY
NORTHWESTERLY FLOW ALOFT WILL BE BETWEEN THE TWO FEATURES AND OVER
OUR AREA. AN ADDITIONAL LONGWAVE TROF WILL MOVE DOWN FROM CANADA
AND BRING COOLER CONDITIONS ESPECIALLY FOR INLAND LOCATIONS BY
NEXT WEDNESDAY. IF THE OPERATIONAL ECMWF VERIFIES, THAT TROF WILL
STAY NEARLY STATIONARY THROUGH THE SECOND HALF OF NEXT WEEK WHICH
WILL HELP TO KEEP COOLER THAN NORMAL READINGS FOR INLAND SPOTS.
&&

.AVIATION...AS OF 10:37 PM PDT THURSDAY...COASTAL LOW CLOUDS
ARE PUSHING INTO COASTAL VALLEYS AND EXPECTED TO REACH ALL
TERMINALS OVERNIGHT. CLEARING IS ANTICIPATED AROUND 17Z FRIDAY
MORNING. WEST WINDS WILL CONTINUE TO EASE OVERNIGHT BECOMING LIGHT
AND LOCALLY VARIABLE ACROSS ALL TERMINALS.

VICINITY OF KSFO...IFR CIGS EXPECTED TO RETURN AFTER 08Z TONIGHT.
CLEARING IS EXPECTED AROUND 17Z-18Z FRIDAY MORNING. LIGHT WEST WINDS
EXPECTED THROUGH THE NIGHT.

KSFO BRIDGE APPROACH...IFR CIGS AFFECTING THE APPROACH AFTER 10Z
FRIDAY MORNING. THE APPROACH WILL SCATTER OUT AROUND 18Z FRIDAY.

MONTEREY BAY AREA TERMINALS...LIFR CIGS EXPECTED TO PERSIST
THROUGH THE NIGHT. CLEARING IS EXPECTED AROUND 17Z FRIDAY MORNING.
LIGHT AND VARIABLE WINDS WILL CONTINUE THROUGH THE NIGHT.

&&

.MARINE...AS OF 9:00 PM PDT THURSDAY...HIGH PRESSURE WILL BUILD
OFF THE NORTHERN CALIFORNIA COAST ON FRIDAY RESULTING IN
INCREASING NORTHWEST WINDS THAT WILL LAST THROUGH THE WEEKEND.
SOUTHERLY SWELL FROM FORMER HURRICANE MARIE WILL GRADUALLY SUBSIDE
THROUGH THE END OF THE WEEK.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PT ARENA TO PT REYES 10-60 NM FROM 6 AM

&&

$$

PUBLIC FORECAST: LARRY
AVIATION/MARINE: CW

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