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

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FXUS66 KMTR 160922

Area Forecast Discussion
National Weather Service San Francisco Bay Area
222 AM PDT Sun Jun 16 2019

.SYNOPSIS...A few degrees of warming is expected for mainly inland
areas on Sunday as high pressure begins to build near the West
Coast. More widespread and significant warming is forecast for
Monday and Tuesday as high pressure strengthens and onshore flow
weakens. However, warming at coastal areas will be limited due to
persistent onshore winds. Seasonable temperatures, along with
areas of night and morning low clouds, are forecast through the
end of next week.


.DISCUSSION...As of 2:22 AM PDT Sunday...The Fort Ord profiler
indicates a marine layer depth of around 2000 feet, and IR
satellite imagery shows coastal stratus has extended well inland
filling inland valleys. Ceilings at area airports range from a few
hundred feet to 1400 feet. Current temperatures are generally
similar to those from yesterday at this time with readings in the
lower 50s to around 60. Highs today are forecast to be a little
warmer than yesterday`s as high pressure aloft begins to build
over the Eastern Pacific and onshore flow weakens. Highs today are
forecast to range from the 60s at the coast to the 70s and 80s

The warming trend will continue early in the week as the upper
ridge over the Eastern Pacific builds eastward over California.
The building high will compress the marine layer, resulting in
less inland development of low clouds and fog by Monday morning,
and especially Tuesday morning. The most significant warming on
Monday and Tuesday will be across inland areas where some
locations could warm to the lower 90s. As a light onshore flow
and marine layer will continue, coastal areas shouldn`t see too
much warming.

Tuesday and Wednesday will likely be the warmest days this week.
Medium range models indicate an upper trough dropping inland to
our east during the second half of the week, pushing the ridge
back offshore. This would bring cooler temperatures back to inland
areas, but remaining slightly above seasonal normals.

&& of 10:40 PM PDT Saturday...Onshore flow continues
to be predominantly east-west but is weaker than yesterday. SFO-
SAC is 3.1 mb compared to 4.7 mb yesterday. So unlike today
stratus will clear out of SFO and OAK but not until the afternoon.
The onshore gradient will weaken further Sunday night as an upper
ridge builds into the Pacific Northwest causing the flow to turn
more northerly. So stratus will be later to arrive.

Vicinity of KSFO...MVFR with bases 1000 feet. Clearing after 20Z.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...IFR cigs through Sunday at MRY. Clearing
after 20Z at SNS.

&& of 10:39 PM PDT Saturday...High pressure off the
northern California coast will keep strong northwest winds
confined to the northern waters through Monday. Light winds can be
expected over the central and southern waters.


     .Tday...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm from 3 PM
             SCA...SF Bay from 1 PM



MARINE: Canepa

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