FXUS66 KMTR 130557
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
957 PM PST Thu Nov 12 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1145 AM PST Thu Nov 12 2026
- Seasonally warm and dry conditions continue today
- Rain returns to the region Friday and into next week
- Coastal flooding due to high tides continues through Friday
- Hazardous beach conditions prevail with dangerous conditions
Saturday
&&
.UPDATE...
Issued at 855 PM PST Thu Nov 12 2026
KMUX radar is showing some showery echoes, mainly off the coast,
but also within the Santa Cruz Mountains and along the Big Sur
Coast. A couple of weather stations within terrain-favored
locations have shown some measurable rain, with the Oak Ridge RAWS
in the Sonoma County coastal ranges reporting 0.05" of rain in
the last couple of hours. Shower activity continues through the
night before the main rain band comes through in the morning
hours.
DialH
&&
.SHORT TERM...
Issued at 1145 AM PST Thu Nov 12 2026
(This afternoon through Friday)
The Bay Area and north Central Coast remains placed between high
pressure extending into the Northern Rockies and a through about
450 miles to the west-northwest. Meanwhile, a cut-off low pressure
is forecast to develop in the next 12 hours and head towards
southern California and Baja California; moving inland by Friday
morning/afternoon. That said, high clouds from the approaching
weather system will be positioned over the region by this
afternoon. This, along with cooling temperatures aloft, will
result in a slight cool down compared to previous days.
Tonight and into early Friday morning, expect light to moderate
rain in the coastal ranges and favored upslope regions along the
coast ahead of the frontal boundary. Southerly winds are forecast
to increase ahead of the cold front overnight with gusts of 25 to
35 mph. Rain will increase in coverage and intensity between 8 AM
- 1 PM Friday across the North Bay, between 10 AM - 3 PM across the
Bay Area and South Bay, and 12 PM - 5 PM across the north Central
Coast. With the cold air mass advecting in from the north, surface
CAPE/most unstable CAPE values of up to 100-300 J/kg will result in
around a 15% potential for thunderstorms. Any heavier rain shower
and/or thunderstorm will be capable of producing brief heavy
downpours, strong and erratic winds, and lightning. Wind gusts have
the potential to reach or exceed 45 mph just ahead of the cold
frontal passage, but are forecast to be short lived as winds
becoming westerly and/or northwesterly in wake of the frontal
passage while also easing. These stronger winds can cause trees or
branches to fall and may result in isolated power outages.
Rain totals from this system (Friday through Saturday afternoon) are
expected to be around 0.5-1.25" for the North Bay (greatest in the
coastal ranges), 0.3-0.8" for the San Francisco Bay Area and
Monterey Bay region, up to 0.75-1.25" for the Santa Cruz Mountains
and the Santa Lucia Range, and 0.1-0.5" for the inland portions of
Monterey and San Benito Counties. Post frontal rain showers are
forecast to persist into Friday evening and early Saturday morning.
Please check the BEACHES section of the AFD for safety tips and more
information on the Beach Hazards Statement/High Surf Warning and
Coastal Flood Advisory.
&&
.LONG TERM...
Issued at 1145 AM PST Thu Nov 12 2026
(Friday night through next Wednesday)
The storm door remains open through the 7 day forecast period! We
are expecting another system to move through the region Sunday into
Monday and a third system to arrive in the middle of the upcoming
week. These systems are not forecast to stall over any one given
area, thus reducing the potential for widespread flooding concerns.
It is a bit to far out in time to talk about thunderstorm potential
and rainfall amounts, yet current forecast do not seem much greater
than the Friday system (1st system to impact the region). Be sure to
stay informed on the latest forecast information as we the storm
door remains open.
&&
.AVIATION...
(06Z TAFS)
Issued at 955 PM PST Thu Nov 12 2026
MVFR conditions are expected as the cold frontal passage moves in
to our forecast area. Moderate to high confidence of ceilings
lowering to MVFR just prior to or shortly after midnight. Strong
southerly winds are expected to persist into mid-day Friday, with
gusts in excess of 35kts possible. Rain is expected to move in to
our forecast area after midnight, most likely in the early morning
hours, expected to slow down as we head into the afternoon. After
frontal passage, rain will become more showery in nature and winds
will start to decrease.
Vicinity of SFO...There is moderate confidence of VFR conditions
shifting to MVFR as we move into the overnight hours and the
front approaches. Southerly winds are expected to continue to
increase overnight, with gusts up to 35kts as we head into Friday
morning. Rain chances are expected to increase to 50% after 15Z,
but confidence on the exact start time continues to remain low.
Late afternoon rain chances will diminish, and winds will start to
decrease into the overnight hours.
SFO Bridge Approach...Winds will be gusty, in excess of 34 knots,
across the SF Bay Friday morning with a Gale Warning in effect
from 9AM to 3PM Friday. Otherwise, similar to SFO.
Monterey Bay Terminals...Currently VFR with conditions to
deteriorate overnight as a moderate band of showers approaches the
region. Scattered showers ahead of the main front will reach MRY and
SNS closer to 15Z with the main band arriving between 18-20Z. It is
possible the band could slow down which would likely delay arrival
by another 1-2 hours. MVFR ceilings, strong southerly winds
gusting to around 30 knots, and light to moderate rain are all
expected as the band arrives. Reduced visibilities, particularly
during heavier showers, are expected during the main frontal
passage. Conditions improve after frontal passage occurs with
winds shifting more west to northwest and decreasing. Scattered
showers remain through the end of the forecast period.
&&
.MARINE...
(Tonight through next Wednesday)
Issued at 955 PM PST Thu Nov 12 2026
Strong to near gale force gusts will continue to strengthen
tonight into Friday morning with gale force gusts becoming more
widespread by mid to late morning as a cold front pushes through
our coastal waters. Localized, occasional storm force gusts are
possible within portions of the Monterey Bay Friday morning into
the afternoon. After frontal passage, winds will shift westerly
and decrease to a moderate breeze by Friday evening. Significant
wave heights will gradually build to up to 30 feet by Saturday
with high seas to continue through much of the weekend due to a
distant hurricane force low. Wave heights decrease slightly
Sunday before increasing again Monday. Small crafts will sustain
heavy damage and may not survive in these extreme sea states.
&&
.BEACHES...
Issued at 1145 AM PST Thu Nov 12 2026
Beach Hazards Statement/High Surf Warning:
A Beach Hazards Statement is in effect through 6 PM Friday, at which
point it gets replaced with a High Surf Warning through 4 AM Sunday.
A series of hurricane force low pressure systems will impact the NE
Pacific through early next week. These storms will produce very high
NW swell that will impact the coast with very hazardous conditions.
Initially the forerunners will bring strong rip currents and sneaker
waves through Friday, while the breaking wave amplitude builds to 15-
20 feet. As the peak of the swell arrives on Saturday, breaking
waves will reach up to 35 feet. Occasional sets of 40-50 ft are
likely at favored breakpoints. These waves bring tremendous power
that will overpower anyone in the water and cause coastal erosion.
The risk of drowning is very high this weekend. Do not go in the
water, avoid climbing on the rocks or leaning over seawalls, and
never turn your back on the ocean. Wave amplitude will abate
somewhat on Sunday before a new round of very high swell arrives
Monday.
Coastal Flood Advisory (Thursday through Friday):
A combination of high astronomical tides and thermal expansion from
warmer than normal water will result in tidal flooding concerns
across Bayshore locations in the San Francisco, San Pablo, and
Monterey Bays. At the San Francisco tide gauge, high tide is
expected to be 1.3 ft above normal (7.1 ft MLLW) at 12:10 PM
Thursday 11/12, 1.5 ft above normal (7.3 ft MLLW) at 12:49 PM Friday
11/13. These predictions include up to 1.8 ft of 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. In addition, long-
period swell will create hazardous conditions along the Pacific
coast beaches with an increased risk of sneaker waves and rip
currents.
Coastal Flood Advisory (Saturday):
The swell on Saturday brings a different variety of coastal flooding
as very large breaking waves pile up along the Pacific coast.
Research shows wave run-up increases the mean water level by 10-20%
of the breaking wave height across exposed beaches. This higher
water elevation sets the stage for large waves to crash over sea
walls and run up beaches onto adjacent infrastructure, particularly
during high tide.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Friday afternoon for CAZ006-505-
509-529-530.
Coastal Flood Advisory until 4 PM PST Friday for CAZ006-506-508-
530.
Coastal Flood Advisory from midnight Friday night to 6 PM PST
Saturday for CAZ006-505-509-529-530.
High Surf Warning from 6 PM Friday to 4 AM PST Sunday for CAZ006-
505-509-529-530.
PZ...Small Craft Advisory until 9 AM PST Friday for Mry Bay-Pigeon Pt
to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Pinos
to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm-
SF Bay N of Bay Bridge.
Gale Warning from 9 AM to 3 PM PST Friday for Mry Bay-Pigeon Pt
to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Pinos
to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm-
SF Bay N of Bay Bridge.
Small Craft Advisory until 3 AM PST Friday for Pt Arena to Pt
Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.
Gale Warning from 3 AM to 9 AM PST Friday for Pt Arena to Pt
Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Rothenberg / Kennedy
MARINE...Kennedy
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Prepared by Boulder-Creek.com Weather at: Thu Nov 12 22:30:03 PST 2026
From the National Weather Service
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