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 192154
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
254 PM PDT SUN APR 19 2015

.SYNOPSIS...COOL CONDITIONS EXPECTED THROUGH TOMORROW ALONG THE COAST
WITH A PERSISTENT MARINE LAYER IN PLACE WHILE INLAND AREAS WARM TO
ABOVE AVERAGE VALUES. A REGION-WIDE COOLING TREND WILL TAKE PLACE
EARLY IN THE WORKWEEK AS A SERIES OF WEAK UPPER LEVEL DISTURBANCES
IMPACT THE STATE. AS A RESULT...UNSETTLED WEATHER WILL BE POSSIBLE
WITH A SLIGHT CHANCE OF SHOWERS THROUGH THE LATTER HALF OF THE
WEEK.

&&

.DISCUSSION...AS OF 3:00 PM PDT SUNDAY...A DEEPER MARINE LAYER
PLUS A STRONGER ONSHORE FLOW AT THE SURFACE HAS LEAD TO COOLER
TEMPERATURES TODAY. CURRENTLY MOST PLACES ARE RUNNING 3 TO 7
DEGREES BEHIND SATURDAY. SHOULD END UP WITH HIGHS IN THE UPPER 50S
TO MID 60S AT THE COAST WITH 70S TO LOWER 80S INLAND. WITH THE
MARINE LAYER EXPECTED TO STAY OVER 2000 FEET TONIGHT AND AN
ONSHORE PUSH AT THE SURFACE...SHOULD SEE ANOTHER ROUND OF CLOUDS
AND PATCHY FOG AROUND THE COAST PLUS INLAND VALLEYS.

TEMPERATURES WILL COOL THROUGH THE WEEK AS A LONGWAVE TROF
ADVANCE TO THE PACNW/BC COASTLINE WHILE AN ASSOCIATED UPPER LEVEL
LOW DROPS DOWN FROM THE NORTH. THIS FEATURE WILL BE WEST OF OUR
COASTAL WATERS BY TUESDAY NIGHT AND WELL TO OUR SW BY WEDNESDAY
EVENING. LAST WEEK THERE WAS CONCERN THAT THE LOW WOULD BRING
SHOWERS TO OUR REGION ALONG WITH POSSIBLE THUNDERSTORMS.
HOWEVER...ALL MODELS ARE IN GOOD AGREEMENT THAT ALMOST ALL OF THE
ASSOCIATED MOISTURE WILL STAY OUT OF OUR AREA. WILL KEEP A MENTION
OF A FEW SHOWERS GOING AS THE ATMOSPHERE WILL BE DESTABILIZED SO
THEY CANNOT BE ENTIRELY RULED OUT. COULD ALSO SEE SOME DRIZZLE
MAINLY ALONG THE COAST. TEMPS WILL RANGE FROM MID 50S TO MID 60S
AT THE COAST WITH MID 60S TO MID 70S FOR INLAND SPOTS. THE COOLER
AND UNSETTLED PATTERN WILL CONTINUE THROUGH AT LEAST SATURDAY.

ECMWF AND GFS SPLIT FOR NEXT WEEK AS THE GFS HAS A LONGWAVE TROF
MOVING INTO OUR AREA BY NEXT MONDAY WHILE THE ECMWF KEEPS ALMOST
ALL OF THE MOISTURE TO OUR NORTH. 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
BOTH INDICATE WETTER THAN NORMAL WEATHER...SO WE COULD POSSIBLY
SEE APRIL ENDING ON A WET NOTE.

&&

.AVIATION...AS OF 10:40 AM PDT SUNDAY...MODERATELY DEEP MARINE
LAYER ALLOWED COASTAL STRATUS TO PUSH INTO INLAND VALLEYS
OVERNIGHT. SLOW CLEARING THIS MORNING BUT EXPECT VFR CONDITIONS
ALL DAY WITH EARLY RETURN TO STRATUS CONDITIONS TONIGHT. LIGHT
ONSHORE FLOW EXPECTED.

VICINITY OF KSFO...VFR THROUGH THE AFTERNOON AND EVENING. MOSTLY
LIGHT WINDS TODAY. STRATUS RETURNS TONIGHT...06-07Z.

SFO BRIDGE APPROACH...MVFR CIGS OVER THE APPROACH THROUGH 19Z.
THEN SIMILAR TO SFO.

MONTEREY BAY AREA TERMINALS...VFR. STRATUS LIKELY RETURNING EARLY
THIS EVENING...BY 02-04Z

&&

.MARINE...AS OF 3:00 PM PDT SUNDAY...A MODERATELY DEEP MARINE
LAYER WILL CONTINUE OVER THE COASTAL WATERS THROUGH EARLY IN THE
WEEK. LIGHT NORTHWEST WINDS AND GENTLE SEA CONDITIONS WILL
CONTINUE THROUGH MONDAY NIGHT. NORTHWEST WINDS ARE FORECAST TO
INCREASE ON TUESDAY AND WEDNESDAY AS LOW PRESSURE DEVELOPS OVER
THE GREAT BASIN AND HIGH PRESSURE STRENGTHENS OFFSHORE.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...NONE.

$$

PUBLIC FORECAST: BELL
AVIATION/MARINE: SIMS

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.