High Surf in California, March 2, 2025

Area Forecast Discussion
National Weather Service San Francisco CA
1036 AM PST Sun Mar 2 2025

...New AVIATION...

.SYNOPSIS...
Issued at 915 AM PST Sun Mar 2 2025

A progressive weather pattern will bring a series of storms to
Northern California this week, with periods wet and unsettled
weather, breezy conditions, and cooler than normal temperatures
prevailing. The first of which will impact the region today and
tomorrow, with a slight chance of thunderstorms possible as well.

&&

.UPDATE...
Issued at 915 AM PST Sun Mar 2 2025

Water vapor imagery shows a beautiful upper level trough draped
over the West Coast this morning, with the upper level low
spinning over the Northern Sacramento Valley at this time. As a
result, transitory scattered showers are continuing to rotate
through the San Francisco and Monterey Bay areas. We have had one
report from the Santa Cruz Mountains of a rain and snow mix above
3000 feet. This makes sense given the temperatures at KMUX at the
time was 33 degrees. We have also had reports of very small hail
from across the Monterey Peninsula. Hourly rainfall totals show
that most areas have received around a tenth of an inch or less,
but a few locations in the Santa Cruz Mountains have received
almost a quarter in the last hour. Overall, rainfall totals so far
in the last 24 hours are a quarter to three-quarters of an inch
in the mountains and upwards of a quarter inch elsewhere.

These scattered showers will continue to be possible today as the
trough lingers over the region. There is a secondary disturbance
moving down the back side of the trough for later this afternoon
and evening, that will likely (60%) enhance the showers activity
as well as bring us a slight chance of thunderstorms. The SPC meso
analysis shows a pretty nice gradient of MU Cape from Sonoma
County southward to Monterey. The HREF highlights areas along and
south of I-80 for the probability of thunder after 18z, and more
focused over the Monterey Bay and San Benito County by 20z. That
said, the best risk of thunderstorms still remains over the
Central Valley, but given the fact that we should easily break the
cap today, do believe we could see some isolated thunderstorms.
The greatest threat with these thunderstorms will be with the
dangerous lightning, small hail and gusty winds. Palmer

&&

.SHORT TERM...
(Today and tonight)
Issued at 346 AM PST Sun Mar 2 2025

Scattered light showers continue to move through the area as the low
pressure moves inland. Keeping an eye on satellite and regional
radar (because KMUX is unfortunately still having issues), there are
some indicators of thunderstorm activity in the marine zones.
However these cells have been losing strength as they approach the
shore, but still have been producing moments of locally moderate to
heavy rain.

The rest of Sunday will see off and on rain chances from passing
showers, with a particular focus on the Big Sur Coast. Thunderstorm
chances will shift from the marine zones to Monterey and San Benito
Counties, with some chances also possible in the East Bay Hills.
These chances peak around 20% in the early afternoon before passing
into the Central Valley. Rain chances finally exit into early Monday
with additional rain totals from this morning through Monday morning
staying on the light side for the interior and more northern
locations. For that same time frame, additional rain adds up to
0.05" to 0.15" for most areas, around 0.30" in the Santa Cruz
Mountains, and 0.40" to 0.80" for the Santa Lucias.

&&

.LONG TERM...
(Monday through Saturday)
Issued at 346 AM PST Sun Mar 2 2025

Dry weather returns Monday afternoon, but it doesn't last as another
rain-maker arrives Tuesday. There has been some back and forth with
the timing and focus of this next event between recent model updates.

Model trends have been reducing the overall strength of the cold
front, leading to more modest initial rainfall. However, the
trailing plum of moisture looks to get picked up by the front's
parent low, and pushed into the Central Coast Tuesday night into
Wednesday as the low center moves across the SF Bay, offering more
scattered rains for that area.

What does that mean? Mostly a meteorologist that was adjusting the
forecast tonight getting too far into the weeds with different model
outputs. But also that the Tuesday through Thursday rains will be
widespread and add up fairly well.

As of the current forecast, the Tues-Thurs rains add up to:

0.25" 0.50" for the Bay Area
0.50" to 1" for the San Mateo Coast and
Monterey and San Benito Counties
1" plus for the Santa Cruz Mts and
Santa Lucias.

As mentioned in previous discussions, there is still some lingering
variability in the mid to long term forecast, so these numbers can
still see some changes. Be sure to keep checking back in.

&&

.AVIATION...
(18Z TAFS)
Issued at 1035 AM PST Sun Mar 2 2025

Mainly VFR conditions should prevail for the rest of this afternoon
and evening. The atmosphere will remain somewhat unstable during
this period which should leave a mid of mid level cu and perhaps
some high cloud passing overhead. The threat for showers will linger
as well, particularly over the Central Coast this afternoon though a
few cannot be ruled out over the Bay Area. West to northwest winds
will continue to pick up today, with sites seeing gusts between 20-
30kt perhaps a few isolated gusts to 35kt. Guidance shows winds
lowering some after 6Z, with the trend gradually continuing through
Monday.

Vicinity of SFO...Mainly VFR conditions should prevail today, with
perhaps an isolated shower or two skirting by. Most CAMS keep SFO
dry after 17-18Z, with a few showing isolated shower potential 19-
20Z ish. Gusty west to northwest winds will then be the story for
SFO, with gusts up to 30kt possible. There is a possibility we could
gust to 35kt though the threat seems a bit more isolated. A few hi-
res models shows lowering cigs around 12Z-18Z tomorrow morning.
Opted to hint at that since confidence was too low to add BKN or OVC
MVFR cigs.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...We're in a showery weather pattern and the
name of the game will be timing over the next 24 hours or so. The
greatest confidence is for a renewed chance this afternoon, with
confidence decreasing as we head into the evening and overnight
hours. VFR conditions should generally prevail, though we could see
brief drops to MVFR cigs in heavier showers. In addition to the
showers, gusty west to northwest winds are forecast through this
afternoon and evening. Winds begin to decrease tonight and into
Monday.
&&

.MARINE...
(Today through Friday)
Issued at 346 AM PST Sun Mar 2 2025

Rain showers and a slight chance for thunderstorms exists today. A
strong northwesterly breeze and rough to very rough seas will
prevail through Monday. Rain returns Tuesday and lingers through
Thursday. Seas build to become rough to very rough again by
Thursday.

&&

.BEACHES...
Issued at 341 AM PST Sat Mar 1 2025

Hazardous beach and marine conditions are expected through Monday
due to building long period westerly swell supporting breaking waves
up to 20 feet. This will be both a beachgoer and a mariner threat.
Everyone should remain out of the water due to life-threatening surf
conditions. Stay off of jetties, piers, and other waterside
infrastructure, keep pets on a leash and away from the water, and
never turn your back on the ocean!

Sarment

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory until 9 PM PST Monday for CAZ006-505-509-530.

     Beach Hazards Statement through Monday evening for CAZ529.

PZ...Small Craft Advisory until 9 AM PST Monday for SF Bay N of Bay
     Bridge.

     Small Craft Advisory until 9 PM PST Monday for Mry Bay-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...Murdock
LONG TERM....Murdock
AVIATION...KR
MARINE...Sarment

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