FXUS66 KMTR 282316
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
416 PM PDT Wed Oct 28 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1227 AM PDT Wed Oct 28 2026
- Moderate coastal flooding at high tide for Bayshore and Pacific
Coast locations through the week
- Seasonal to slightly below seasonal temperatures through the
extended forecast
- Potential for rain this weekend and again early to mid next
week
&&
.SHORT TERM...
Issued at 142 PM PDT Wed Oct 28 2026
(This evening through Thursday night)
The sun is out across the Bay Area and Central Coast this
afternoon, but you would not know it by looking at the
temperatures. Seasonably cool conditions prevail across the
region thanks to a relatively cool airmass overhead (850mb temps
below normal). Despite the cooler than normal temps, it's still a
pleasant afternoon with temps mainly in the 60s and a few 70s
across the far interior.
This evening through Thursday night - Longwave pattern overview
shows much of the West Coast under the influence of broad upper
trough and a robust upper low anchored over the PacNW. Flowing
into the upper trough is a decaying, weaker upper low due west of
the Bay Area. This feature is helping to spread some high level
clouds over the Central Coast this afternoon. Expect clouds to
increase over the region tonight. The cloud cover will lead to
slightly warmer overnight lows compare to this morning. For
Thursday, still seasonably cool with similar afternoon
temperatures. The PacNW upper low slow drifts southward through
the day. As this happens, the decaying upper low interacts with an
embedded shortwave trough rounding the base of the broad upper
trough. As such, a few CAMs develop modeled radar reflectivity
over the Bay Area tomorrow. Resolved QPF is showing zero. As
such, forecast will reamin dry for now, but it's possible for
KMUX radar to show a few echoes tomorrow afternoon (probably
virga at best).
&&
.LONG TERM...
Issued at 240 PM PDT Wed Oct 28 2026
(Friday through next Tuesday)
To round out the work week the southward drift of the upper low
continues with further deepening of the broad upper trough.
Temperatures cool a few degrees in response to the deepening
trough and onshore flow.
Now for the big question in the long term: will it rain and will
it impact Halloween? The answer is yes, but not a lot and not
everywhere. Early on Saturday the deepening trough will get a
boost from a cyclonically enhance jet max moving in SoCal/Central
Coast. This will help to facilitate cyclogenesis. The developing
offshore sfc low will then take aim at SoCal. The northern fringe
of this system will have the greatest chance for impacts to the
Central Coast leaving the heart of the Bay Area less likely for
precip Saturday afternoon into Sunday. The forecast as of now
brings some light rain to the Central Coast Saturday afternoon and
then spreading chances slightly northward by Saturday evening
with rain chances ending by early Sunday. Basically
Hollister/Santa Cruz northward will be little (a few showers) to
no precip and areas southward a few hundredths to three tenths of
an inch. Simply put, Bay Area doen't be surprised so see a few
drops if you have outdoor activities planned for Halloween.
Monterey Bay region and southward don't be surprised to see light
rain or a few showers.
Dry weather briefly returns Sunday into Monday with a slight warm
up due to ridging.
Tuesday and beyond are lower confidence forecast as the EPac
remains active, but details vary depending upon model of choice.
Given the uncertainty, we do have a few chances for precip, but
nothing noteworthy at this time. A few weak systems nose their
way into a ridge.
Coastal flooding concerns continue across Bayshore locations within
the San Pablo, San Francisco, and Monterey Bays through Saturday
and the Pacific coastal regions through Friday. At the San
Francisco tidal gauge, high tide is expected to be 1.9 ft above
normal (7.7 ft MLLW) at 01:43 PM Thursday 10/29, 1.6 ft above
normal (7.4 ft MLLW) at 02:39 PM Friday 10/30, and 1.1 feet above
normal (6.9 ft MLLW) at 03:44 PM on Saturday 10/31, including
around 1.2 ft of surge residual partially attributed to impacts
from El Nino.
&&
.AVIATION...
(00Z TAFS)
Issued at 416 PM PDT Wed Oct 28 2026
Afternoon and early evening onshore winds will become light and
variable then light offshore tonight and Thursday morning. Surface
high pressure over far northern California and the Great Basin will
weaken by later Thursday. High and mid level clouds will gradually
increase tonight and Thursday, reducing radiative cooling tonight
and radiative warming Thursday. VFR is forecast in the 00z TAFs.
Vicinity of SFO...VFR. West wind 10 to 12 knots decreasing to
light west to northwest wind then shifting to light northeast
Thursday morning. West to northwest wind 10 knots Thursday
afternoon and early evening.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. West to northwest winds near 10
knots becoming light and variable then light east to southeast
tonight and Thursday morning. West to northwest winds near 10
knots Thursday afternoon and early evening.
&&
.MARINE...
(Tonight through next Monday)
Issued at 408 PM PDT Wed Oct 28 2026
Moderate to strong northwest winds continue into the night across
the outer waters with fresh to moderate breezes along coastal
waters, with seas continuing to build in response and resulting in
rough seas over exposed waters. Expect gradually improving
conditions by Thursday and into the early part of the weekend. A
long period west-northwest swell is forecast to arrive late this
weekend and into early next week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 6 PM PDT Saturday for CAZ006-506-
508-529-530.
Coastal Flood Advisory until 5 PM PDT Friday for CAZ505-509.
PZ...Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt
to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos
to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 PM PDT Thursday for Pt Arena to Pt
Reyes 10-60 NM.
Small Craft Advisory until 3 PM PDT Thursday for Pigeon Pt to Pt
Pinos 10-60 NM.
&&
$$
SHORT TERM...MM
LONG TERM....MM
AVIATION...Canepa
MARINE...RGass
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Prepared by Boulder-Creek.com Weather at: Wed Oct 28 16:30:04 PDT 2026
From the National Weather Service
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