FXUS66 KMTR 042324
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
324 PM PST Sun Jan 4 2026

...New AVIATION, MARINE, BEACHES...

.KEY MESSAGES...
Updated at 129 PM PST Sun Jan 4 2026

 - Rain coming to an end today, mostly dry tonight.

 - Another round of light-to-moderate rain expected Monday morning
   with scattered showers during the afternoon.

 - Light scattered showers into midweek, then high confidence in
   fair weather the wrap up the week into the weekend.

&&

.SHORT TERM...
Issued at 129 PM PST Sun Jan 4 2026
(This evening through Monday)

Quite the episode of rain this morning here at NWS MTR. A few
areas from the Monterey Peninsula to Hollister reported 1-2 inches
of rain this morning with Monterey Airport coming in at 2.15"
since midnight. Elsewhere around the Bay Area reports range from
about 0.5-1" depending on where you are north to south and in
relation to rain shadowing terrain. Some lingering rain showers in
the vicinity of the SF Bay are moving out this afternoon, and most
people should see the sun at some point this afternoon/evening.

Moving on to tomorrow, we're anticipating another round of
rainfall beginning in the pre-dawn hours for the North Bay and Bay
Area, then the Monterey Bay and Central Coast around sunrise. This
does seem to be a more progressive line of showers as opposed to
the training showers that we had this morning. However, with soils
at or near saturation in some areas, flooding concerns will arise
easily. We are NOT expecting any widespread, damaging winds with
tomorrow's system, but as mentioned regarding the state of the
soil, trees will be more likely to fall under lesser magnitude
winds than would normally be required. After the main band of
morning rainfall, we'll see some scattered showers into the
afternoon with a small potential for an isolated thunderstorm over
the waters. The showers at this point should be mostly
unproblematic outside of one or two isolated strong showers that
may exacerbate already existing flooding impacts. In terms of
thunderstorms, there is some instability into the afternoon 
hours which could lead to more vigorous updrafts over the waters,
but don't really see the threat really making it very far onto 
land. To that point, the wind field is nearly uniform up to almost
500 mb, so there will be very little, if any, shear to support
persistent updrafts. The primary threat continues to be isolated
nuisance flooding and shallow landslides.

&&

.LONG TERM...
Issued at 129 PM PST Sun Jan 4 2026
(Monday night through next Saturday)

Conditions dry out Monday night giving way to mostly clear skies
Tuesday with just a few lingering light showers. Beyond this and
through the rest of the week the story turns to cold overnight 
temperatures and absolutely gorgeous, albeit chilly, afternoons.
Ensemble cluster analysis strongly supports broad, high amplitude
ridging in the long term. For overnight lows, it looks like the
coldest period will be Thursday through Monday mornings with the
peak cold being Friday morning (Thursday night) where widespread
30s are likely inland with mid-to-lower 40s along the coast.

&&

.AVIATION...
(00Z TAFS)
Issued at 322 PM PST Sun Jan 4 2026

Isolated to scattered showers are expected through the rest of the 
evening, as ceilings rise to generally low-end VFR-MVFR across the 
region. Widespread rain returns overnight into Monday with generally 
moderate rain rates, localized heavy rain, and diminished 
visibilities expected. Southerly flow continues through the TAF 
period with periods of gusty winds expected as the main rain band 
comes through. Visibilities and ceilings will drop below the TAF 
forecast if a strong shower moves over a particular terminal.

Vicinity of SFO... Scattered showers continue over the terminal this 
evening before light to moderate rain returns in the pre-dawn hours 
Monday morning, conditions hover near the MVFR-VFR threshold. 
Showers will again diminish in intensity Monday evening through 
the end of the TAF period. Visibilities and ceilings will drop 
below the TAF forecast if a strong shower moves over SFO.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals... Breezy westerly flow continues through the 
evening as generally VFR-MVFR conditions and isolated showers 
continue. Southerly winds return overnight as a frontal rain band 
approaches, with the main impacts arriving Monday morning, including 
gusty southeast winds and light to moderate rain. Rain intensity 
should diminish Monday afternoon through and after the end of the 
TAF period. If more intense showers develop over the region, expect 
visibilities and ceilings to drop below the forecast within the
TAF. 

&&

.MARINE...
(Tonight through next Friday)
Issued at 322 PM PST Sun Jan 4 2026

Rain and a slight chance of thunderstorms continue today with
showers expected to continue through Monday. Hazardous conditions
for small crafts continue due to hazardous seas between 10 to 13
feet. Seas abate tonight but hazardous conditions continue as
winds strengthen to strong to gale force. Winds diminish by early
next  week but are expected to build again, along with seas,
during the  late week as long period northwesterly swell returns.

&&

.BEACHES...
Issued at 322 PM PST Sun Jan 4 2026

A Coastal Flood Advisory has been extended through 3 PM Monday 
for the San Francisco Bay and San Pablo Bay due to Perigean 
spring tides (king tides) and up to 1 foot of storm surge. The 
combination of these factors will bring minor to moderate coastal 
flooding to the low-lying areas near shorelines and tidal 
waterways during high tide on Monday late morning and early 
afternoon.

High tide is expected to be 1.2 ft above normal at 12:08 PM 
Monday. These predictions include up to 1 foot of storm surge 
that will enhance the astronomical tide and flooding threat. High 
tide varies up to 90 minutes earlier or later along the Pacific 
Coast and through the San Francisco Bay, respectively.

A Beach Hazard Statement is in effect Sunday through 10 PM. Large
swell will impact the Pacific beaches, generating large breaking 
waves up to 20 feet, strong rip currents, and sneaker waves. 
Inexperienced swimmers should avoid the water. Nobody should climb
the coastal rocks. Never turn your back on the ocean.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement until 10 PM PST this evening for CAZ006-
     505-509-529-530.

     Coastal Flood Advisory until 3 PM PST Monday for CAZ006-506-508.

PZ...Small Craft Advisory from 3 AM to 9 PM PST Monday for Mry Bay.

     Small Craft Advisory until 3 PM PST Monday for Pt Arena to Pt 
     Reyes 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 9 PM PST Monday for Pigeon Pt to Pt 
     Pinos 0-10 nm.

     Small Craft Advisory until 9 AM PST Monday for Pt Arena to Pt 
     Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Gale Warning from 9 AM to 3 PM PST Monday for Pt Pinos to Pt 
     Piedras Blancas 0-10 nm.

     Small Craft Advisory until 9 PM PST this evening for Pigeon Pt 
     to Pt Pinos 10-60 NM.

     Small Craft Advisory from 9 AM to 9 PM PST Monday for Pigeon Pt 
     to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...DialH
MARINE...Kennedy

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Prepared by Boulder-Creek.com Weather at: Sun Jan 4 16:30:03 PST 2026