Weather Service Report


576 
FXUS66 KMTR 050418
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
918 PM PDT WED MAY 4 2016

.SYNOPSIS...MOSTLY CLOUDY AND COOL CONDITIONS WILL PERSIST
THROUGH LATE WEEK AS AN UPPER LEVEL SYSTEM APPROACHES THE COAST.
THIS FEATURE WILL ALSO RESULT IN ISOLATED TO SCATTERED SHOWERS AND
THE POTENTIAL FOR ISOLATED THUNDERSTORMS THROUGH SATURDAY. DRY
WEATHER CONDITIONS WILL LIKELY RETURN BY SUNDAY AND PERSIST INTO
NEXT WEEK ALONG WITH A SLIGHT WARMING TREND AS HIGH PRESSURE
BUILDS OVER THE EASTERN PACIFIC.

&&

.DISCUSSION...AS OF 9:11 PM PDT WEDNESDAY...AN UPPER LEVEL CLOSED
LOW CENTERED AT APPROXIMATELY 36N 127W OFF THE CENTRAL CALIFORNIA
COAST HAS MAINTAINED A STEADY STREAM OF MID AND UPPER LEVEL
CLOUDS ACROSS THE REGION TODAY. TEMPERATURES FELL 5 TO 10 DEGREES
FROM YESTERDAY AS A RESULT OF THE INCREASED CLOUD COVER AND A COOLER
AIRMASS MOVING IN. THE LATEST BLENDED PRECIPITABLE WATER IMAGE
SHOWS PW OF AROUND AN INCH EXTENDING FROM THE PACIFIC NORTHWEST
SOUTHWARD ALONG THE LENGTH OF THE CALIFORNIA COAST. THE BULK OF
THE MOISTURE PLUME CURRENTLY SIT OFF THE COAST HOWEVER AS THIS
SYSTEM SHIFT FURTHER EAST AND CONTINUES TO ADVECT MOISTURE
NORTHWARD ALONG ITS EASTERN FLANK THE PLUME OF MOISTURE WILL MOVE
INLAND ACROSS THE DISTRICT. THIS WILL RESULT IN INCREASED CHANCE OF
PRECIPITATION TONIGHT AND THURSDAY. A FEW ISOLATED THUNDERSTORMS
AND NUMEROUS LIGHTNING STRIKES WERE OBSERVED TODAY OUTSIDE OF OUR
WARNING AREA. THE CHANCE OF ISOLATED THUNDERSTORMS IS ANTICIPATED
THURSDAY AFTERNOON AS THE CENTER OF THE LOW MOVES EAST TOWARD AND
THEN ACROSS SOUTH-CENTRAL CALIFORNIA. INCREASED INSTABILITY AND
MOISTURE WILL LEAD TO SCATTERED SHOWERS AND ISOLATED AFTERNOON
THUNDERSTORMS CAPABLE OF PRODUCING SMALL HAIL.

BY FRIDAY THE LOW IS FORECAST TO MOVE TO THE SOUTH OF OUR CWA
RESULTING IN UNSETTLED WEATHER ACROSS OUR AREA. SHOWERS WILL
LINGER INTO SATURDAY AS MOISTURE CONTINUES TO CIRCULATE AROUND
THIS SYSTEM. SHOWERS WILL BE HIT AND MISS ACROSS THE REGION WITH
ACCUMULATION ANYWHERE FROM A TENTH TO A QUARTER OF AN INCH WITH A
FEW LOCATION POSSIBLY RECEIVING UP TO A HALF INCH.

TEMPERATURES WILL REMAIN BELOW SEASONAL AVERAGES THROUGH SATURDAY
AS THE UPPER LOW REMAINS IN THE VICINITY. WARMER AND DRIER WEATHER
IS FORECAST TO RETURN SUNDAY AS A RIDGE OF HIGH PRESSURE BEING TO
BUILD IN OVER THE EASTERN PACIFIC. MILD AND DRY CONDITIONS ARE
EXPECTED TO CONTINUE INTO THE FIRST HALF OF THE WORK WEEK. 

&&

.AVIATION...AS OF 5:10 PM PDT WEDNESDAY...UPPER LOW WAS CENTERED
ABOUT 250 MILES WEST OF KMRY LATE WEDNESDAY AFTERNOON WITH ALL
SHOWER AND THUNDERSTORM ACTIVITY OCCURRING WELL TO THE NORTH AND
EAST OF THE TAF SITES. ACCORDING TO MOST MODEL
DATA...SHOWERS/THUNDERSTORMS CHANCES WILL REMAIN VERY LOW UNTIL
THURSDAY AFTERNOON WHEN CHANCES WILL INCREASE AS THE LOW
APPROACHES THE CENTRAL CALIFORNIA COAST. UNTIL THEN...MAIN CONCERN
IS LOW CLOUDS. MVFR CIGS WILL LIKELY DEVELOP AT MOST TERMINALS
OVERNIGHT AND PERSIST THROUGH MIDDAY FRIDAY. WINDS LIGHT TO
MODERATE FROM THE WEST AND SOUTHWEST.

VICINITY OF KSFO...VFR THROUGH 04Z WITH MODERATE WSW WINDS. MVFR
CIGS EXPECTED TO DEVELOP AROUND 04Z AND PERSIST THROUGH THURSDAY
MORNING. CONFIDENCE MODERATE. SHOWERS MAY DEVELOP IN VICINITY OF
THE TERMINALS ON THURSDAY AFTERNOON. WINDS WSW AROUND 12 KT
THROUGHTHE EVENING BECOMING LIGHT OVERNIGHT.

SFO BRIDGE APPROACH...SIMILAR AS KSFO.

MONTEREY BAY TERMINALS...VFR UNTIL ABOUT 02Z WITH MVFR CIGS
EXPECTED THEREAFTER AND UNTIL LATE THURSDAY MORNING. MODERATE WSW
EARLY IN PERIOD BECOMING LIGHT AND VARIABLE OVERNIGHT.

&&

.MARINE...AS OF 8:56 PM PDT WEDNESDAY...AN UPPER LOW CENTERED
WEST OF MONTEREY BAY WILL MOVE SLOWLY EAST AND INLAND ACROSS
CENTRAL CALIFORNIA BY LATE IN THE WEEK. THIS LOW WILL RESULT IN
MODERATE NORTHERLY WINDS IN THE OUTER WATERS NORTH OF PT REYES AS
WELL AS A CHANCE OF SHOWERS. LIGHT WINDS WILL PREVAIL ELSEWHERE.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PT ARENA TO PIGEON PT 10-60 NM
             SCA...SF BAY UNTIL 9 PM

&&

$$

PUBLIC FORECAST: CW
AVIATION: DYKEMA
MARINE: DRP


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