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

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000
FXUS66 KMTR 301137
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
437 AM PDT WED JUL 30 2014

.SYNOPSIS...MONSOON/SUBTROPICAL MOISTURE WILL CONTINUE TO FILTER
IN OVER THE FORECAST AREA TODAY. THE AIRMASS WILL BEGIN TO DRY
TONIGHT AND BY THURSDAY FOR SLIGHTLY COOLER AND LESS HUMID
CONDITIONS. THEN...NEAR NORMAL TEMPERATURES CAN BE EXPECTED
THROUGH THE REMAINDER OF THE WEEK.

&&

.DISCUSSION...AS OF 3:03 AM PDT WEDNESDAY...SATELLITE IMAGERY
SHOWS A VARIETY OF CLOUDS ACROSS THE STATE WITH STRATUS OVER THE COASTAL
WATERS AND LOCALLY INLAND...HIGH CLOUDS MOVING ACROSS MONTEREY AND SAN
BENITO COUNTIES...REMNANTS FROM EX-TROPICAL DEPRESSION HERNAN...AND
A FEW SHOWERS/THUNDERSTORMS OVER THE SIERRA FOOTHILLS AND NORTHERN
SONOMA AND MENDOCINO COUNTIES. LATEST LIGHTNING DETECTION HAS
PICKED UP RECENT STRIKES OVER MENDOCINO COUNTY. SO FAR NO STRIKES
OVER SONOMA COUNTY ALTHOUGH WE STILL HAVE A SLIGHT CHANCE OF
THUNDERSTORMS IN THE FORECAST INTO THE MORNING HOURS.

THE LATEST COMPUTER MODELS INDICATE STRONGER NORTHWEST WINDS
DEVELOPING OVER THE OCEAN BEGINNING TONIGHT ...THEN INCREASING AND
SPREADING SOUTH BY THURSDAY NIGHT. THE ONSHORE SURFACE PRESSURE
GRADIENT IS PROGGED TO TIGHTEN SUBSTANTIALLY BY TONIGHT...WITH
OVER 4 MB BETWEEN SFO AND SAC BY THIS EVENING PER THE NAM12. AS A
RESULT...A COOLING TREND IS EXPECTED TO BEGIN TONIGHT AND THURSDAY
AS STRONGER ONSHORE FLOW DEVELOPS. THIS PATTERN IS THEN FORECAST
TO PERSIST THROUGH THE REMAINDER OF THE FORECAST PERIOD WITH NEAR
NORMAL TEMPERATURES EXPECTED OVER THE WEEKEND AND INTO NEXT WEEK.

&&

.AVIATION...AS OF 4:30 AM PDT WEDNESDAY...SATELLITE FOG PRODUCT
INDICATES A DECENT STRATUS DECK ALONG THE COAST AND LOCALLY
INLAND. JUST LIKE THE LAST FEW MORNINGS HIGH CLOUDS CONTINUE TO
STREAM IN FROM THE SOUTH AS WELL. THE MARINE DEPTH IS 1000-1300
FEET THIS MORNING WITH CIGS AOB 1K FEET AT A FEW TERMINALS.
COVERAGE THIS MORNING IN SAN FRANCISCO BAY IS A LITTLE MORE THAN
YESTERDAY GIVEN BETTER COOLING ABOVE MARINE INVERSION. THAT BEING
SAID...DO EXPECT STRATUS TO IMPACT MORE OF SAN FRANCISCO BAY THIS
MORNING. THE SHALLOW NATURE WILL ALSO HELP FOR A CLEARING TIME OF
16-17Z. MAINLY VFR THIS AFTERNOON AT ALL TERMINALS. STRATUS COMES
BACK IN AGAIN TONIGHT.


VICINITY OF KSFO...SATELLITE TRENDS AND HI-RES MODELS INDICATE
THAT STRATUS SHOULD EVENTUALLY FILL IN AND IMPACT KSFO FOR A FEW
HOURS THIS MORNING. CONF IS NOT THE HIGHEST...BUT DID DECIDE TO
INCLUDE IT IN THE TAF. VFR CONDITIONS THIS AFTERNOON WITH GUSTY
ONSHORE FLOW.

KSFO BRIDGE APPROACH...CIGS WILL LIKELY IMPACT PARTS OF THE
APPROACH EVEN IF SMB ISN`T REPORTING A CIG. CLEARING SHOULD BE
RELATIVELY EARLY.

MONTEREY BAY AREA TERMINALS...IFR CIGS THROUGH 16-17Z. VFR THIS
AFTERNOON...BUT EARLY RETURN THIS EVENING.

&&

.MARINE...AS OF 04:24 AM PDT WEDNESDAY...HIGH PRESSURE OVER THE
EASTERN PACIFIC WILL MAINTAIN NORTHERLY FLOW ALONG THE CENTRAL
COAST. WINDS WILL BE LOCALLY GUSTY NORTH OF POINT REYES TODAY. THE
SEA STATE WILL CONTINUE TO BE GENTLE THROUGH THE REMAINDER OF THE
WEEK.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...SF BAY NORTH OF THE BAY BRIDGE FROM 1 PM
             SCA...SF BAY SOUTH OF THE BAY BRIDGE FROM 1 PM

&&

$$

PUBLIC FORECAST: SIMS
AVIATION/MARINE: MM

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