760
FXUS66 KMTR 050008
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
408 PM PST Sat Jan 4 2025

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1259 PM PST Sat Jan 4 2025

A dry pattern is settling in with warmer temperatures and
offshore winds expected next week.

&&

.SHORT TERM...
(This evening through Sunday)
Issued at 1259 PM PST Sat Jan 4 2025

High clouds are streaming across the area related to a cold front
impacting the Pacific Northwest. While these clouds should provide
a great sunset, high pressure over northern California will keep
any other impacts well north of the Bay Area. Overnight
temperatures will remain mild for most. The ridge amplitude will
continue to build through the day Sunday, increasing the
temperature and decreasing the cloud coverage. Sunday is going to
be beautiful as a result. Ample sunshine, comfortable
temperatures in the 60s (about 5 degrees warmer than today), and
light winds. Not bad for January. Apparently it`s National Bird
Day, why not grab the binos and see what`s in the neighborhood
trees? Maybe go to Pinnacles and look for Condors?

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 1259 PM PST Sat Jan 4 2025

The weekend ridge will remain entrenched next week, allowing the
850 mb temperature to climb from around 10C to 15C from Monday
through Friday, or from the 75th to 95th percentile for this time
of year. While the ridge remains along the Pacific coast through
the week, a fast moving disturbance will create a positively
tilted trough across the Rocky Mountains. Ensemble cluster
analysis shows there is a 80% chance this disturbance becomes a
cut-off low near NW Mexico in the Tuesday-Wednesday time frame.
This will support an "inside slider" pattern, with very strong
Santa Ana winds in the Southern California mountains near the low
pressure center. They have gotten very little rain in Southern
California this year, and a Fire Weather Watch is in effect for LA
and Ventura counties. Locally, we will have less impactful
weather in the Bay Area, but are still expecting strong to gale
force Diablo winds. Fortunately our recent rains make these dry,
offshore winds much less concerning. That said, it`s not out of
the question for a wind advisory to be issued, depending on the
exact track of the disturbance. The forecasted SFO-WMC pressure
gradient has decreased a bit from yesterday, but is still
expected to reach -10 to -12 mb, or around the 99th percentile.

Both the GFS and ECMWF ensembles show the next chance for any
significant rain isn`t until the 15th or 16th. Literally no
members of either ensemble have more than a trace of
precipitation. If that`s true, it would be the first time since
the heart of the drought in 2015 that downtown San Francisco
recorded no precipitation from Jan 4th through Jan 15th.

&&

.AVIATION...
(00Z TAFS)
Issued at 404 PM PST Sat Jan 4 2025

VFR through the TAF period for all but the STS and HAF which will
see pockets of fog into early Sunday morning. Winds will be limited
to local effects for several sites, meaning light and mostly
variable winds for much of the area aside from moderate north and
northwest winds in the afternoons. Widespread VFR returns into late
Sunday morning.

Vicinity of SFO...VFR through the TAF period. Moderate northwest
winds become light and variable into the night. Expect moderate west-
northwest winds to build again into mid Sunday afternoon before
easing into that night.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR through the TAF period. Winds stay
mostly light for MRY, but SNS keeps moderate winds into the night
before reducing.


&&

.MARINE...
(Tonight through next Friday)
Issued at 404 PM PST Sat Jan 4 2025

Hazardous conditions for small craft continues with rough seas and
moderate northwesterly swell through early Sunday morning with
significant wave heights between 12-13 feet. Seas ease briefly
Sunday  afternoon, then begin to build again into the next work
week.

&&

.BEACHES...
Issued at 1219 PM PST Thu Jan 4 2025

Wave model forecasts indicate long period westerly swell arriving
along the coastline from Sonoma County to Monterey County Friday
night, decreasing to a moderate period westerly swell Saturday. We
have issued a Beach Hazard Statement from 9 AM Friday to 9 PM
Friday due to increased risk for sneaker waves. Then, High Surf
Advisory from 9 PM Friday to 3 AM Sunday due to breaking waves of
18-25 feet (all coastal locations expect the northern Monterey Bay
which will remain in a Beach Hazard Statement).

Also at the current time, wave model forecasts are showing a newly
arriving long period westerly swell Monday into Tuesday. As always
whenever there is increasing surf - remember to never turn your back
on the ocean and stay out of the water. Again please stay tuned to any
further updates for late week, additionally for early next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory until 3 AM PST Sunday for CAZ006-505-509-530.

     Beach Hazards Statement until 3 AM PST Sunday for CAZ529.

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

     Small Craft Advisory until 3 AM PST Sunday for Pigeon Pt to Pt
     Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

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

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