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000
FXUS66 KMTR 111731
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1031 AM PDT TUE MAR 11 2014

.SYNOPSIS...BREEZY OFFSHORE WINDS ARE EXPECTED TO DEVELOP LATER
THIS AFTERNOON LASTING THROUGH THE OVERNIGHT HOURS. THE STRONGEST
WINDS ARE EXPECTED TO OCCUR OVER THE NORTH AND EAST BAY HILLS.
HOWEVER MIXING WILL PROMOTE GUSTS REACHING INTO SOME VALLEY
LOCATIONS. A RIDGE OF HIGH PRESSURE WILL CONTINUE TO BUILD OVER
THE EAST PACIFIC AND WEST COAST. THIS BUILDING RIDGE WILL RESULT
IN A WARMING TREND WHICH WILL PERSIST THROUGH THE UPCOMING WEEKEND
WITH AFTERNOON TEMPERATURES IN THE UPPER 60S AND MID 70S AT THE
COAST AND MID 70S TO UPPER 80S INLAND SATURDAY AND SUNDAY.

&&

.DISCUSSION...AS OF 9:46 AM PDT TUESDAY...MOSTLY SUNNY SKIES ARE
EXPECTED TODAY AS A RIDGE OF HIGH PRESSURE BUILDS OVER THE
FORECAST AREA AND OFFSHORE WINDS DEVELOP AT THE SURFACE. THE
COMBINATION OF CLEAR SKIES AND OFFSHORE FLOW WILL RESULT IN
AFTERNOON HIGH TEMPERATURES IN THE UPPER 60S TO LOW 70S ALONG THE
COAST WITH MID 70S INLAND. AS TEMPERATURES WARM UP ATMOSPHERIC
MIXING WILL RESULT IN GUSTY EAST NORTHEAST WINDS IN THE AFTERNOON
AND EVENING. MODERATE TO STRONG WINDS ARE EXPECTED TO DEVELOP
ACROSS THE NORTH BAY MOUNTAINS THIS EVENING PROMPTING A HIGH WIND
ADVISORY FOR THAT AREA WHICH WILL BE ISSUED SHORTLY.

THE 0000Z ECMWF AND THE 1200Z GFS40 HAVE INITIALIZED WELL WITH THE
CURRENT SYNOPTIC PATTERN AND REMAIN IN GOOD AGREEMENT THROUGH AT
LEAST SUNDAY MORNING. BOTH MODELS ARE BUILDING A RIDGE OF HIGH
PRESSURE OVER THE EASTERN PACIFIC WITH AN INSIDE SLIDER PUSHING
SOUTH ALONG THE SIERRA INTO SOUTHERN NEVADA TONIGHT. AT THE
SURFACE THIS WILL RESULT IN A FAIRLY STRONG OFFSHORE SURFACE
PRESSURE GRADIENT. THE 1200Z NAM12 AND GFS40 AS WELL AS OUR HIGHER
RESOLUTION MODELS ARE INDICATING THAT 925MB WINDS WILL REACH 40 TO
50 KT ACROSS THE NORTH BAY MOUNTAINS THIS EVENING LASTING INTO THE
OVERNIGHT HOURS. THEREFORE WILL BE ISSUING A WIND ADVISORY FOR THE
NORTH BAY MOUNTAINS SHORTLY. BY WEDNESDAY MID MORNING THE LOW
PRESSURE SYSTEM PUSHES FURTHER SOUTH EAST AND THE SURFACE PRESSURE
GRADIENT BEGINS TO WEAKEN RESULTING IN DECREASING OFFSHORE WINDS.

ACCORDING TO THE FORECAST MODELS THE RIDGE OF HIGH PRESSURE BEGINS
TO SLIDE EAST FRIDAY PUSHING 500MB HEIGHTS TO AROUND 576 TO 579 DM
ALONG THE COAST. BY SATURDAY THE RIDGE BUILDS TO AROUND 580DM OVER
THE SAN FRANCISCO BAY AREA. THIS BUILDING RIDGE WILL PROMOTE A
WARMING TREND WITH AFTERNOON HIGH TEMPERATURES REACHING THE MID
70S TO LOWER 80S INLAND AND LOW TO MID 70S ALONG THE COAST. WITH
GENERALLY LIGHT OFFSHORE WINDS AT THE SURFACE IT LOOKS LIKE A
GREAT TIME TO GET OUT AND ENJOY THE OUTDOORS FROM MID WEEK THROUGH
THE WEEKEND! JUST REMEMBER TO DRINK PLENTY OF WATER AND USE SUN
SCREEN.


&&

.AVIATION...AS OF 10:30 AM PDT TUESDAY...VFR CONDITIONS WILL
PREVAIL THROUGH THE FORECAST. BREEZY NORTHEAST WINDS WILL CONTINUE
OVER THE NEXT FEW HOURS...BEFORE BRIEFLY TURNING ONSHORE EARLY
THIS AFTERNOON. WINDS WILL SWITCH ONCE AGAIN TO A NORTHEAST
DIRECTION LATER THIS EVENING INTO THE OVERNIGHT HOURS.

VICINITY OF KSFO...VFR.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...VFR.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...PT ARENA TO PT REYES 10-60 NM UNTIL 3 PM
             SCA...PT REYES TO PIGEON PT 10-60 NM UNTIL 3 PM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 3 PM

&&

$$

PUBLIC FORECAST: LARRY
AVIATION: RILEY

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