Small Craft Advisory 4, NWS San Francisco Bay Area, CA

Area Forecast Discussion
National Weather Service San Francisco CA
1239 AM PST Sun Jan 4 2026

...New SHORT TERM, LONG TERM, BEACHES...

.KEY MESSAGES...
Updated at 117 PM PST Sat Jan 3 2026

 - One last day of coastal flooding from king tides

 - Chance of thunderstorms today

 - Hazardous beach conditions through tonight

 - Daily rain showers expected through Monday

&&

.SHORT TERM...
Issued at 1202 AM PST Sun Jan 4 2026
(Today and tonight)

The unsettled weather continues as another cold front approaches
the coast over the next 12 hours. Scattered showers are becoming
more organized and numerous through the morning. There have been a
few lightning strikes over the coastal waters in the last 30
minutes, and the environment looks able to support this convection
over the Bay Area through the early morning. The heavier band of
rain will gradually slide south over the next few hours, focusing
impacts on San Mateo and Santa Cruz through midday. Heavier
showers will likely lead to nuisance flooding and possible
landslides. If the thunderstorms make it to land, it's unlikely
they will produce severe wind gusts or tornadoes. There is still
several hundred J/kg of CAPE, but the low level shear has
decreased below 10 kts, too weak to support tornadogenesis. Garden
variety thunderstorms still bring hazards, namely lighting
strikes, heavy downpours and small hail. Shower activity will
gradually decrease through the evening before the next round on
Monday.

&&

.LONG TERM...
Issued at 1202 AM PST Sun Jan 4 2026
(Monday through Saturday)

High resolution models are showing a brief break in the rain
between Sunday evening and early Monday morning as a dry slot
moves through after frontal passage. The moisture will quickly
recharge as a low pressure system moves near the coast. This
system will flip the dry post-frontal NW winds to moist SW'rly
flow. Monday will be another wet one. Everyone should pick up
another 1-2" from now until Tuesday morning. At that point the low
will weaken in place. There's a lot of uncertainty regarding
Tuesday. Since the low isn't really moving, it's hard to pin down
exactly what will happen to the associated moisture. Our official
QPF forecast dries out starting Tuesday, but there's still a
decent probability of precipitation through even Wednesday. By
Thursday high pressure will confidently move in, shutting down
rain chances and clearing up the weather for the weekend. Low
temperatures will respond to the clearing skies thanks to enhanced
radiational cooling at night. Many inland areas will be dropping
back into the 30s starting Thursday morning and we should see some
frost Friday. As a high amplitude ridge builds, the dry weather
looks to settle in place, with no significant chance of rain
through the end of next week.

&&

.AVIATION...
(06Z TAFS)
Issued at 909 PM PST Sat Jan 3 2026

Scattered light showers continue with moderate to breezy southerly
winds. Shower activity increases into the night, then become more
widespread with a another frontal boundary Sunday morning and into
the afternoon. Expect reduced visibilities along the leading edge of
the front from increased rain rates, with visibilities struggling to
recover in the post-frontal environment between lingering showers
and pockets of fog and mist trapped in the valleys. Shower activity
reduces into late Sunday afternoon and evening, but slight chances
look to last through that night and rebuild again Monday morning.

Vicinity of SFO...Light scattered showers continue to move through
the area with breezy southerly winds. Winds reduce into the night,
while shower activity increases slightly. This will cause slight
reductions in visibilities. Rain chances build again in the mid
morning as the next front arrives, with persistent showers expected
in the wake of the front through the afternoon. Rain chances reduce
again into Sunday evening, but spotty showers continue to be
possible. More widespread and persistent rain is expected to return
mid-morning on Monday.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Light showers are mostly staying along the
Santa Lucias and along the Big Sur coast, but a few will pass near
the terminals through the evening. Chances for rain continue through
the night and increase ahead of the next front into the mid morning.
Rain rates, and some trapped moisture will cause reductions in
visibilities as the front moves through, and in the post-frontal
environment. Winds and rain chances reduce late Sunday afternoon
with cloud cover beginning to scatter.

&&

.MARINE...
(Tonight through next Friday)
Issued at 835 PM PST Sat Jan 3 2026

Showers and a slight chance of thunderstorms continue through the
rest of the weekend. Breezy to gusty winds linger through the rest
of the weekend across the waters, with hazardous swells for
smaller craft at 12 to 16 feet that abate early next week. Expect
mostly light winds and seas into the work week with some showers
on Monday. Winds and seas build again into the late week.

&&

.BEACHES...
Issued at 117 PM PST Sat Jan 3 2026

A Coastal Flood Advisory is in effect for the San Francisco Bay,
San Pablo Bay, Pacific Coast, and Monterey Bay through 2 PM Sunday
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 late Sunday morning.

High tide is expected to be 1.9 ft above normal at 11:18 AM
Sunday. 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...Coastal Flood Advisory until 2 PM PST this afternoon for CAZ006-
     505-506-508-509-529-530.

     Beach Hazards Statement from 6 AM PST this morning through this
     evening for CAZ006-505-509-529-530.

PZ...Small Craft Advisory until 9 AM PST this morning for Mry Bay.

     Small Craft Advisory until 9 PM PST this evening for Pigeon Pt
     to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena
     to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos
     to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

&&

SHORT TERM...Flynn
LONG TERM....Flynn
AVIATION...Murdock
MARINE...Murdock

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Preliminary Local Storm Report
National Weather Service San Francisco CA
936 PM PST Sat Jan 3 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0920 AM     Coastal Flood    3 NW Monterey           36.63N 121.92W
01/03/2026                   Monterey           CA   NWS Employee

            Delayed report, approximate time. Water was
            flowing over the swim deck at Lovers Point
            Beach.

&&

DH

Preliminary Local Storm Report
National Weather Service San Francisco CA
937 PM PST Sat Jan 3 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1052 AM     Coastal Flood    2 N San Francisco       37.81N 122.42W
01/03/2026                   San Francisco      CA   Public

            Corrects previous flood report from 2 N San
            Francisco. Delayed report. Video posted on
            social media showed high tides causing water
            to reach the surface of the piers to the
            west of Hyde Street Piers.

&&

DH

Preliminary Local Storm Report
National Weather Service San Francisco CA
1245 AM PST Sun Jan 4 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1206 AM     Non-Tstm Wnd Dmg 1 WSW Deer Park         38.53N 122.48W
01/04/2026                   Napa               CA   Law Enforcement

            Large tree blocking NB lane.

&&

DJF

Preliminary Local Storm Report
National Weather Service San Francisco CA
109 AM PST Sun Jan 4 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0102 AM     Non-Tstm Wnd Dmg 5 W Saratoga            37.26N 122.12W
01/04/2026                   Santa Clara        CA   Law Enforcement

            Large tree blocking NB land.

&&

DJF