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

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS66 KMTR 301818
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1018 AM PST FRI JAN 30 2015

.SYNOPSIS...DRY CONDITIONS ARE EXPECTED TO CONTINUE INTO NEXT
WEEK WITH CHANCES OF RAIN ONLY OVER FAR NORTHERN CALIFORNIA.
TEMPERATURES WILL REMAIN SEVERAL DEGREES ABOVE NORMAL FOR THE NEXT
WEEK.

&&

.DISCUSSION...AS OF 09:31 AM PST FRIDAY...
MORNING FOG AND LOW CLOUDINESS AGAIN PRESENT IN THE AREA VALLEYS.
DENSE FOG HAS BEEN REPORTED AT SEVERAL LOCATIONS AND VISIBILITY
HAS RANGED FROM BELOW 1/4 OF A MILE TO 1/2 OF A MILE IN THE WORST
SPOTS. THE LATEST VISIBLE SATELLITE IMAGERY SHOWS EROSION OF THE
LOW CLOUDS AND FOG BUT THE ENTIRE LENGTH OF THE SANTA CLARA
VALLEY...THE NORTHERN HALF OF THE SALINAS VALLEY...AND THE SF BAY
AND A WEST DELTA AREAS REMAIN SOCKED IN. CONDITIONS WILL IMPROVE
BY LATE MORNING AND A DENSE FOG ADVISORY REMAINS THROUGH 11 AM.
OTHERWISE SUNNY...DRY...AND WARM CONDITIONS WILL CONTINUE WITH
TEMPERATURES REMAINING ABOVE NORMAL.

&&

.PREV DISCUSSION...AS OF 3:14 AM PST FRIDAY...STRATUS IS SETTING UP
ALONG THE COAST AND STARTING TO PUSH INTO THE BAY AREA. CURRENTLY
THE AREAS PICKING UP FOG ARE LIMITED TO THE NORTH BAY
VALLEYS...BUT EXPECT PATCHY FOG IN MORE PLACES BY MORNING. CURRENT
TEMPERATURES ARE RUNNING MAINLY IN THE 40S ACROSS THE DISTRICT
EXCEPT AROUND SFO AND ON PENINSULA WHERE LOWER 50S ARE OCCURRING.
HIGHS TODAY ARE EXPECTED TO BE IN THE 60S TO LOWER 70S.

TONIGHT WHEN AN UPPER LOW NOW OVER SOCAL MOVES TO THE EAST...A
SURFACE HIGH WILL MOVE OVER THE NORTHERN GREAT BASIN WHICH WILL
INCREASE NORTHERLY WINDS OVER THE HILLS. THE LATEST NAM12
INCREASES 925MB WINDS TO AROUND 30 KNOTS OVERNIGHT TONIGHT AND
SATURDAY MORNING MAINLY OVER THE NORTH AND EAST BAY HILLS.

MEANWHILE...NORTHERN CALIFORNIA REMAINS UNDER A STAGNANT WEATHER
PATTERN WITH AN UPPER RIDGE NOSING INTO THE PACIFIC NORTHWEST AND
OVER NORTHERN CALIFORNIA. THE HIGH PRESSURE RIDGE WILL CONTINUE TO
SHUNT ALL RAIN CHANCES WELL NORTH OF OUR DISTRICT THROUGH THE
FORECAST PERIOD. IN ADDITION...HIGH TEMPERATURES ARE EXPECTED TO
BE ABOVE NORMAL THROUGH THE PERIOD.

MEDIUM RANGE MODELS CONTINUE TO HOLD ONTO SOME HOPE FOR RAIN
POSSIBLY SPREADING INTO NORTHERN CALIFORNIA BY LATE NEXT WEEK.
BOTH THE ECMWF AND GFS BRING RAIN TO NORTHERN CALIFORNIA BEGINNING
NEXT FRIDAY AND SATURDAY. THE GEM...HOWEVER...KEEPS THE RIDGE
INTACT FOR CONTINUED DRY CONDITIONS FOR NORTHERN CALIFORNIA.

&&

.AVIATION...AS OF 10:00 AM PST FRIDAY...PATCHY DENSE FOG AND
STRATUS PREVAILED ACROSS MUCH OF THE BAY AREA THIS MORNING.
VISBILITIES HAVE IMPROVED BUT  THE LOW CLOUDS ARE EXPECTED TO LINGER
A LITTLE LATER INTO THE MORNING... ESPECIALLY IN THE NORTHERN SANTA
CLARA VALLEY AND WEST DELTA. VFR CONDITIONS WITH LIGHT WINDS FORECAST
FOR THIS AFTERNOON WITH NO MORE THAN A FEW CLOUDS PRESENT IN THE SKY.

VICINITY OF KSFO...FEW TO SCT LOW CLOUDS IN THE VICINITY OF KSFO
THROUGH THE MORNING WITH VFR CONDITIONS. THE PRIMARY IMPACT WILL
COME FROM STRATUS OVER THE SOUTH BAY NEAR KSMB.

CONFIDENCE IS MODERATE.

KSFO BRIDGE APPROACH...LOW CLOUDS ACROSS THE SOUTH BAY MAY IMPACT
LOS ON APPROACH. SATELLITE IMAGERY IS ONLY SHOWING DISSIPATION OF
CLOUD DECK AT THIS POINT... SO WOULD NOT BE SURPRISED TO SEE LOW
CLOUDS LINGER UNTIL 1930-20Z.

MONTEREY BAY AREA TERMINALS...VFR THROUGH THE DAYLIGHT HOURS.
MARINE STRATUS INTRUSION LATE TONIGHT WILL LEAD TO POSBL IFR CIGS
BTWN 04Z-16Z.

CONFIDENCE IS MODERATE.

&&

.MARINE...AS OF 09:59 AM PST FRIDAY...MODERATE NORTH WINDS WILL
CONTINUE OVER THE COASTAL WATERS THROUGH SATURDAY. THE STRONGEST
WINDS WILL BE AT LEAST 10 NAUTICAL MILES OFFSHORE OF THE COAST.
PATCHY DENSE FOG WILL LINGER ACROSS THE NORTH BAY AND WEST DELTA
THROUGH NOON TODAY. THE COMBINATION OF MODERATE WINDS AND SWELL
MAY RESULT IN SOMEWHAT CHOPPY SEAS AS WELL. WIND AND SEA
CONDITIONS ARE EXPECTED TO IMPROVE BY TOMORROW AFTERNOON.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...DENSE FOG ADVISORY...NORTH BAY VALLEYS...SF BAYSHORE...SANTA
                                  CLARA VALLEY.
             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
             MARINE FOG ADVISORY...SF BAY NORTH OF THE BAY BRIDGE UNTIL NOON

&&

$$

PUBLIC FORECAST: JOHNSON
AVIATION: DRP
MARINE: LARRY

VISIT US AT WEATHER.GOV/SANFRANCISCO

FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.