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

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000
FXUS66 KMTR 030545
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1045 PM PDT TUE JUN 2 2015

.SYNOPSIS...DRY WEATHER WILL PERSIST THROUGH AT LEAST THURSDAY WITH
TEMPERATURES GENERALLY BELOW SEASONAL AVERAGES. AN UPPER LEVEL LOW
WILL BRING THE POSSIBILITY OF SHOWERS THIS WEEKEND.

&&

.DISCUSSION...AS OF 9:47 PM PDT TUESDAY...TEMPERATURES TODAY WERE
FAIRLY CLOSE TO NORMAL...WITHIN 2 TO 3 DEGREES OF NORMAL FOR EARLY
JUNE. THE THEME WAS PRETTY MUCH WARMER TEMPERATURES INLAND VALLEYS
AS WELL AS COOLER TEMPERATURES AT THE IMMEDIATE COAST COMPARED TO
YESTERDAY`S READINGS.

A WEAK UPPER LEVEL TROUGH OVER NORTHERNMOST CA CONTINUES TO MOVE
EAST AND WILL REACH NW NEVADA EARLY WEDNESDAY MORNING. IN THE INTERIM
A DEEPER TROUGH OVER THE EASTERN PACIFIC WILL APPROACH THE BAY AREA
AND CENTRAL COAST LATE TONIGHT THROUGH WEDNESDAY LOWERING 500 MB
HEIGHTS. THE TROUGH WILL BECOME A CLOSED OFF MID LEVEL LOW CIRCULATION
LATE WEDNESDAY NIGHT AND CONTINUE TO MOVE SOUTH REACHING THE CENTRAL
COAST THURSDAY AFTERNOON. THERE`S ONLY SPOTTY VERY LIGHT QPF AMOUNTS
FORECASTED BY THE MODELS THROUGH MID TO LATE WEEK...BASICALLY NEXT TO
DRY AREA-WIDE. INCREASED AMPLIFICATION IN THE 500 MB HEIGHT PATTERN
ACROSS THE GULF OF ALASKA TO THE PACIFIC NORTHWEST WILL PRODUCE AN
UNSTABLE RIDGE AND AGEOSTROPHIC JET STREAM WINDS OVER THE TOP OF THE
RIDGE WILL ENTER THE BACK SIDE OF THE CLOSED UPPER LOW OVER CA POSSIBLY
STALLING THE LOW`S FORWARD PROGRESSION...AT LEAST TEMPORARILY. FORECAST
CONFIDENCE REGARDING THE LOW`S PROGRESSION IS LOW TO MODERATE BY LATE
WEEK.

&&

.AVIATION...AS OF 10:45 PM PDT TUESDAY...THE NORTHERLY SURFACE
GRADIENT FROM SFO-ACV HAS INCREASED ONE MB TO 4.9 MB THIS EVENING
CLEARING ANY LINGERING STRATUS FROM THE COAST. LOW CLOUDS ARE EXPECTED
TO RETURN LATE TONIGHT. HOWEVER THE SWATH OF HIGH CLOUDS CURRENTLY
STRETCHED ACROSS THE REGION IS MAKING IT HARD TO SEE EXACTLY WHAT
IS GOING ON BENEATH THIS LAYER. LATEST OBS SHOW A FEW LOW CLOUDS
OVER AREA TERMINALS WITH EXCEPTION TO KMRY THAT IS OVC012. STRATUS
WILL SCATTER OUT BY NOON WEDNESDAY. GUSTY ONSHORE FLOW WILL
RETURN AGAIN WEDNESDAY AFTERNOON. MODERATE CONFIDENCE.

VICINITY OF KSFO...IFR CIGS ARE ANTICIPATED TO RETURN AROUND 08Z
AND 10Z OVER KOAK AND KSFO RESPECTIVELY. CIGS WILL SCATTER OUT
AROUND 19Z. MODERATE ONSHORE FLOW BETWEEN 10 TO 15 KT WITH GUSTS
TO NEAR 20 KT WILL CONTINUE THROUGH LATE TONIGHT OVER KSFO. WINDS
WILL EASE TO UNDER 10 KT OVERNIGHT. GUSTY SEABREEZE WILL RETURN
AGAIN WEDNESDAY AFTERNOON.

KSFO BRIDGE APPROACH... SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...IFR CIGS HAVE FILLED IN OVER KMRY
WITH KSNS EXPECTED TO GO IFR AROUND 10Z TONIGHT. CLEARING IS
EXPECTED AROUND 18Z-19Z WEDNESDAY. LIGHT SOUTH TO SOUTHWEST WINDS
AROUND 5 TO 10 KT EXPECTED OVERNIGHT. GUSTY SEABREEZE WILL RETURN
AGAIN WEDNESDAY AFTERNOON.

&&

.MARINE...AS OF 9:00 PM PDT TUESDAY...HIGH PRESSURE BUILDING OVER
THE EASTERN PACIFIC WILL GENERATE MODERATELY STRONG WINDS ACROSS
THE COASTAL WATERS. GUSTY WINDS WILL PERSIST THROUGH FRIDAY WITH
HAZARDOUS CONDITIONS AND STEEP WIND WAVES.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PIGEON PT TO PT PINOS 0-10 NM
             SCA...PT ARENA TO PT REYES 0-10 NM
             SCA...PT REYES TO PIGEON PT 0-10 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
             SCA...PT ARENA TO PT REYES 10-60 NM
             SCA...PT REYES TO PIGEON PT 10-60 NM
             SCA...PIGEON PT TO PT PINOS 10-60 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
             SCA...MONTEREY BAY UNTIL 3 AM

&&

$$

PUBLIC FORECAST: CANEPA
AVIATION/MARINE: CW

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