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

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FXUS66 KMTR 241131

Area Forecast Discussion
National Weather Service San Francisco Bay Area
431 AM PDT Wed May 24 2017

.SYNOPSIS...A cooling trend can be expected through Friday as
high pressure weakens and the marine influence increases. Minor
warming is then expected during the upcoming weekend into early
next week as high pressure returns to the West Coast.

&& of 3:30 AM PDT Wednesday...Another round of
widespread clouds at the coast plus through most of the Salinas
Valley and into much of San Francisco Bay. Marine layer continues
to be around 1,500 feet along with a moderate onshore flow (SFO-
SAC gradient over 3 MB) at the surface. Clouds will burn-off
toward the coast later this morning although similar to the past
few days, some locals beaches will not see any sunshine.

Biggest change compared to yesterday will be cooler conditions
inland as an upper level low and associated longwave trough
continue to dive southward into the Northern Rockies. Highs will
only be in the 70s to the lower 80s for inland locations with
upper 50s to upper 60s closer to the coast. The influx of cooler
air will lead to breezy conditions during the afternoon. Another
round of coastal clouds can be expected tonight.

Additional inland cooling is forecast for Thursday and Friday as
the trough dives farther to the south. Far inland spots will
struggle to get into the 70s while coastal areas will be in the
mid 50s to the mid 60s.

A ridge of high pressure will rebuild across our region starting
on Saturday and continuing at least into Monday. Many inland
locations will return to the upper 70s to around 90. Clouds along
with a continued onshore flow will keep towns near the coast
considerably cooler.

No sign of rainfall through the first week of June.


.AVIATION...As of 4:30 AM PDT Wednesday...Deep stratus intrusion
this morning, bringing widespread VLIFR to IFR cigs to most TAF
sites. Generally speaking, marine layer is both deeper and has
lower ceilings this morning and will take longer to mix out today
versus yesterday. Some locations, ie along immediate coast such as
KHAF and KMRY will likely remain OVC010 or less through the entire
day. Otherwise, increasing west to southwest winds along the
coast becoming breezy to occasionally gusty in the

Vicinity of KSFO...IFR to MVFR cigs thru the mid morning, mixing
out to VFR between 18-19Z. Tower will have better conditions than
the bridge which could impact approach until late morning. W-SW
winds up to 15kt with gusts to the low 20kts.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...Stratus through the day along the coast,
with mixing out by mid to late morning further inland. Breezy
southwest winds through the afternoon and evening. Ceilings down
to 200-300 ft this morning/tonight.

&& of 04:25 AM PDT Wednesday...Increasing southerly
winds along the coast today. surface high pressure bringing
northerly winds further offshore north of point reyes. a small
northwest swell moves through the water this week.


     .Tday...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...SF Bay from 9 AM




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