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 211530
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
830 AM PDT THU AUG 21 2014

.SYNOPSIS...WARMER TEMPERATURES ARE EXPECTED AWAY FROM THE COAST
THE NEXT FEW DAYS. OTHERWISE LITTLE CHANGE IS FORECAST THROUGH THE
WEEKEND WITH CONTINUED BELOW NORMAL TEMPERATURES EXPECTED...ESPECIALLY
FOR INLAND AREAS. MUCH WARMER INLAND TEMPERATURES ARE POSSIBLE BY
THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...AS OF 08:30 AM PDT THURSDAY...WIDESPREAD LOW CLOUDS
AGAIN THIS MORNING. THE MARINE LAYER DEPTH IS DOWN TO AROUND 2100
FEET SO CLOUDS SHOULD BE A BIT QUICKER TO BURN OFF THIS MORNING.
SOUTHERLY FLOW PERSISTS BRINGING MOST OF THE STRATUS INTO THE NORTH
BAY WHILE LEAVING THE SANTA CLARA VALLEY MOSTLY CLEAR.
TEMPERATURES ARE CURRENTLY A COUPLE OF DEGREES COOLER THAN AT THIS
TIME YESTERDAY MORNING HOWEVER THE INCREASED CLEARING THIS
AFTERNOON WILL LEAD TO SEVERAL DEGREES OF WARMING INLAND. FORECAST
CALLS FOR SIMILAR WEATHER TO CONTINUE INTO THE WEEKEND AND IS ON
TRACK...NO MAJOR UPDATES ARE ANTICIPATED THIS MORNING.

&&

.PREV DISCUSSION...AS OF 3:00 AM PDT THURSDAY...SOUTHERLY FLOW IN THE
LOW LEVELS HAS CAUSED STRATUS TO PILE UP IN THE NORTH BAY THIS
MORNING. LOCAL DRIZZLE IS POSSIBLE IN THESE AREAS DURING THE EARLY
MORNING HOURS. THE MARINE LAYER IS STEADILY COMPRESSING AS UPPER
LOW OVER SOUTHERN CALIFORNIA MOVES EAST AND UPPER LEVEL HIGH
OVER THE EASTERN PACIFIC NUDGES INTO THE STATE. THIS WILL ALLOW
FOR MORE AFTERNOON CLEARING AND ABOUT 4-8 DEGREES OF WARMING INLAND
ON THURSDAY. ANOTHER UPPER TROUGH WILL DEEPEN OVER THE PACIFIC
NORTHWEST TONIGHT AND FRIDAY AND WILL MAINTAIN A MARINE LAYER OF
1500-2000 FEET OVER THE AREA. UPPER LEVEL TROFFING WILL CONTINUE
OVER THE PACIFIC NORTHWEST THROUGH THE WEEKEND BEHIND THE
ORIGINAL UPPER TROUGH. AS A RESULT TEMPERATURES WILL COOL OFF
SLIGHTLY FRIDAY THROUGH SUNDAY AND BE NEAR OR SLIGHTLY BELOW NORMAL.

PREVIOUS MODEL RUNS SUGGESTED SIGNIFICANT WARMING AROUND NEXT
TUESDAY AS UPPER LEVEL HIGH FROM THE EASTERN PACIFIC MOVES
OVER THE STATE. THE LATEST MODELS MAINTAIN THIS SCENARIO EXCEPT
THE ECMWF HOLDS OFF THE HEATING UNTIL WEDNESDAY. SO THE EXTENDED
FORECAST STILL CALLS FOR SEVERAL DEGREES OF WARMING FOR THE
MIDDLE OF NEXT WEEK.

&&

.AVIATION...AS OF 4:43 AM PDT THURSDAY...THE MARINE LAYER IS
APPROXIMATELY 2000 FEET DEEP THIS MORNING WITH BASES RANGING
BETWEEN 800 AND 1200 FEET. THERE IS CURRENTLY A HOLE IN THE
STRATUS AROUND KSFO AND THE APPROACH BUT THIS HOLE MAY FILL IN BY
1400Z PERSISTING FOR A FEW HOURS. OVERALL TODAY IS MORE OF A
TYPICAL STRATUS PATTERN COMPARED TO YESTERDAY SO EXPECTING TYPICAL
LATE MORNING BURN OFF AT THE TERMINALS.

VICINITY OF KSFO...SCT-BKN018 IS EXPECTED TO PERSIST THROUGH 1730Z
WITH A POSSIBILITY OF BKN012 CIGS PASSING OVER THE TERMINAL
BETWEEN 1400 AND 1600Z. THE SEA BREEZE IS EXPECTED TO REACH 10 TO
15 KT THIS AFTERNOON.

CONFIDENCE IS MODERATE.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...OVC008-012 WILL PERSIST THROUGH
1800Z THIS MORNING AT WHICH POINT VFR IS ANTICIPATED. THE SEA
BREEZE WILL REACH 10 TO 12 KT THIS AFTERNOON.

CONFIDENCE IS MODERATE.

&&

.MARINE...AS OF 3:00 AM PDT THURSDAY...A WEAK SURFACE PRESSURE
GRADIENT WILL MAINTAIN GENERALLY LIGHT WINDS ACROSS A MAJORITY OF
THE COASTAL WATERS TODAY. MODERATE WINDS ARE EXPECTED OVER THE
NORTHERN OUTER WATERS. THE SURFACE PRESSURE GRADIENT IS EXPECTED
TO INCREASE FRIDAY...RESULTING IN STRENGTHENING WINDS. A MODERATE
PERIOD SOUTHERLY SWELL GENERATED BY TROPICAL STORMS WILL MOVE INTO
THE REGION LATER THIS WEEK.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...SF BAY NORTH OF THE BAY BRIDGE FROM 2 PM

&&

$$

PUBLIC FORECAST: AC/W PI
AVIATION/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.