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

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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

FXUS66 KMTR 122100

Area Forecast Discussion
National Weather Service San Francisco Bay Area
100 PM PST Mon Nov 12 2018

.SYNOPSIS...Smoke will continue to impact the region through at
least early this week with dry conditions and light offshore
winds. Seasonably mild, dry conditions will then persist through
much of the week and into the upcoming weekend. A pattern change
will potentially bring rainfall to the region around Thanksgiving.

&& of 01:00 PM PST Monday...Not a lot has changed
from this morning - heavy smoke continues to blanket much of the
region with moderate to unhealthy air quality. The smoke is also
impacting temperatures and have adjusted many locations a few
degrees downward to due decreased sun.

Only minor day to day changes are expected with the over sensible
weather for much of the upcoming week. High pressure aloft will
gradually shift eastward and weaken roughly midweek. In the short
term, smoke will continue to impact much of the region keeping
temperatures slightly cooler. The extent of smoke coverage is a
little tricky as a lot will depend on how much smoke is produced
from the Camp Fire and minor shifts in the surface winds.
Overnight lows will continue to drop to in the 30s at night for
interior valleys. Current forecast will include some patchy frost
for locations colder than 33 degrees, but not widespread enough
for a frost advisory.

The million dollar question continues to be, where`s the rain? It
seems like the longer range models have been fine tuning a pattern
shift, but keep kicking it farther down the road. The last few
days the targeted pattern shift has been early next week into
Thanksgiving. The latest 12z model suite still shows this thinking
with a trough and possible rain next week. However, the GFS and
ECMWF are at odds with details and timing. Conf still remains low.
None the less, latest official seven day forecast will bring some
light rain to the North Bay late Tuesday with slightly cooler
temps. CPC 8-14 day outlook is now showing higher than normal
chance for a wetter pattern as well for CA. Stay tuned.


.AVIATION...As of 9:34 AM PST Monday...For 18z TAFs. Wildfire
smoke continues to be the main concern today with IFR/MVFR vis and
occasional BKN cigs through the period. Slant range vis will
remain a major issue. The latest HRRR smoke model shows little to
no improvement in conditions through tonight. Generally light
offshore flow will continue.

Vicinity of KSFO...Light SE/NE winds will persist through the
period. Smoke will continue to be the main concern with MVFR vis
and FEW to SCT cigs around 2500-3500 feet.

SFO Bridge Approach...Similar to KSFO. Major smoke impacts due to
slantwise problems. Latest HRRR smoke forecast shows little to no
improvement through tonight.

Monterey Bay Terminals...Easterly winds through this morning
before winds turn onshore this afternoon. Stronger southerly winds
being observed at KSNS around 15 kt will lessen towards the
afternoon as winds turn onshore.

&& of 08:22 AM PST Monday...Generally light to moderate
southerly winds will continue today and tomorrow as a system
passes by to the north. Winds will  transition back out of the
northwest mid-week as high pressure  builds back in over the
eastern Pacific. Light mixed swell will  continue through mid-week
before a northwest swell arrives.





Visit us at

Follow us on Facebook, Twitter, and YouTube at: is the U.S. government's official web portal to all federal, state and local government web resources and services.