772
FXUS66 KMTR 191142
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
342 AM PST Sun Jan 19 2025

...New SYNOPSIS, SHORT TERM, LONG TERM, AVIATION...

.SYNOPSIS...
Issued at 340 AM PST Sun Jan 19 2025

Offshore winds are forecast Monday into Tuesday morning, with the
strongest winds being favored over the North Bay. A Wind Advisory
was issues for the North Bay mountains where gusts of 35 to 50 mph
are expected, though the highest peaks may see gusts closer to 50 to
60 mph. Outside of these winds, dry weather persists through the
forecast period. Daytime temperatures will gradually be warming this
week and morning lows remaining chilly.

&&

.SHORT TERM...
(Today and tonight)
Issued at 340 AM PST Sun Jan 19 2025

Another night of spectacular satellite imagery has been gifted to
us. The signal is reminiscent of our summertime pattern with fog and
stratus snaking through the valleys and meandering over our waters.
This trend will likely continue through the early morning hours
before mixing out later this morning or by early afternoon. The
forecast remains on a partial repeat for one more night, with the
return of fog and stratus. This should onset early this evening but
clear out by the late evening or early overnight hours due to
increasing offshore winds.

&&

.LONG TERM...
(Monday through Saturday)
Issued at 340 AM PST Sun Jan 19 2025

The pattern change begins Sunday night into Monday morning, as
offshore flow develops. Upper level troughing will be situated over
much of the central U.S. with a shortwave trough sliding down the
Great Basin and into the Desert Southwest Monday into Tuesday.
Guidance continues to come into agreement that gusty winds will
develop over the greater Bay Area mountains and hills. The strongest
winds will be observed in the North Bay mountains, where gusts of 50
to 60 mph are expected at the highest of peaks and gusts of 35 to 50
mph can be expected elsewhere. A Wind Advisory has been issued for
this area from 4AM Monday to 1AM Tuesday. Gusty winds to around 25
to 35 mph are likely to develop across the East Bay hills and along
the San Francisco/San Mateo Peninsula during the same time frame.
Fire concerns remain low as fuel moistures remain high thanks to
rainfall from earlier this winter.

Beyond Tuesday, look for dry weather to persist with a gradual
warming trend for our high temperatures. Most inland areas will see
temperatures rise to the mid to upper 60s, with temperatures closer
to the mid to upper 50s along the coast and for areas of higher
elevation. Mornings will remain chilly, with temperatures spanning
the 30s to the low 40s. We will need to keep an eye out for
additional frost advisories during this.


Following the trend of where is our rain? Perhaps in the distant
future. Ensembles try to hint at the possibility of rain this coming
weekend as an upper level trough is expected to pass over the
western U.S.. Looking at the ensembles, chances overall look to be
rather slim. The NBM may be too ambitious with the 10-30% it has
speckled over our service area, but it`s not an awful reputation.
This unfortunately doesn`t jive with the CPC 6-10 or 8-14 day
outlook where it advertises below normal chances of precipitation.
The 3-4 week outlook, which puts us in the first half of February
has more positive signal of 50-55% chance of above normal
precipitation for much of our area.


&&

.AVIATION...
(12Z TAFS)
Issued at 340 AM PST Sun Jan 19 2025

Currently seeing a mixed bag of LIFR-VFR across the board with fog
and stratus rapidly expanding. All terminals are expected to
experience LIFR-IFR conditions through the morning with the lowest
confidence in LVK. High confidence in VFR at all terminals by this
afternoon with the exception of HAF as an IFR ceiling is expected to
linger. LIFR fog at APC and STS and MVFR ceilings at MRY and SNS are
expected tonight, but it will be short lived as offshore develops by
12Z Monday.

Vicinity of SFO...Currently VFR with a westerly breeze and stratus
quickly closing in. IFR conditions are expected to prevail through
the morning with a return to VFR expected by this afternoon. Winds
will prevail out of the west through the day with offshore flow on
tap beginning tomorrow morning.

SFO Bridge Approach...San Mateo Bridge Approach is currently clear;
however, stratus is quickly expanding northwestward from SJC and
southeastward from the San Pablo and San Francisco Bays.

Monterey Bay Terminals...Currently IFR with easterly flow at both
terminals. High confidence in VFR conditions at both terminals by
this afternoon with MVFR conditions returning tonight.

&&

.MARINE...
(Today through Friday)
Issued at 226 AM PST Sun Jan 19 2025

Moderate seas and moderate northwesterly breezes will prevail
today with high pressure continuing to support dry conditions and
fog/low clouds during the overnight periods. Strong offshore
breezes will create hazardous conditions for small craft Monday
and Tuesday.

&&

.BEACHES...
Issued at 226 AM PST Sun Jan 19 2025

A long period westerly swell with a period of 22 seconds is
resulting in a moderate to high risk of sneaker waves and an
increased risk of rip currents. For beachgoers to remain safe it is
vital to keep off of jetties and rocks, keep pets on a leash,
observe the ocean for 20 minutes before recreating on the beach or
in the ocean, and never turn your back on the ocean. A Beach Hazards
Statement is in effect for all Pacific Coast beaches through 7 PM
Monday.

Sarment

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Monday evening for CAZ006-505-
     509-529-530.

     Wind Advisory from 4 AM Monday to 1 AM PST Tuesday for CAZ504.

     Frost Advisory until 9 AM PST this morning for CAZ516>518.

PZ...Small Craft Advisory from 3 AM Monday to 3 AM PST Tuesday for SF
     Bay N of Bay Bridge.

     Small Craft Advisory from 3 AM to 9 AM PST Monday for Pt Reyes
     to Pigeon Pt 0-10 nm.

     Small Craft Advisory from 9 PM Monday to 3 AM PST Tuesday for Pt
     Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory from 9 PM this evening to 9 AM PST Monday
     for Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...KR
LONG TERM....KR
AVIATION...Sarment
MARINE...Sarment

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