572
FXUS66 KMTR 112339
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
339 PM PST Sat Jan 11 2025

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 107 PM PST Sat Jan 11 2025

Dry conditions a forecast for the upcoming week, along with chilly
morning temperatures. Periods of gusty offshore winds will be
possible through the early portion of the work week.

&&

.SHORT TERM...
(This evening through Sunday)
Issued at 107 PM PST Sat Jan 11 2025

Zonal flow becomes influences by broad upper level troughing aloft
as it slowly encompasses much of the west. At the surface, high
pressure builds. Main tweaks to the forecast for this period were
the wind and then tonight`s low temperatures. We`re still on track
to see breezy offshore winds for our North Bay Interior Mountains,
East Bay Hills, Santa Cruz Mountains, and Eastern Santa Clara Hills.
Gusts up 30 to 40 mph will be possible, with stronger gusts possible
for higher elevations. Winds begin to ease Sunday morning and fall
below Wind Advisory criteria by the early afternoon perhaps sooner.
Moving to the forecast, took some time to review last night`s low
temperature forecast and the observations across the area. Opted to
blend in some of the NBM 75th percentile and last night`s
observations for tonight`s temperature. That put`s the southern
Salinas Valley and interior San Benito County within Frost Advisory
criteria again tonight. Interior Monterey will get chilly as well
but may not see as widespread of lows. Will need to keep an eye on
the temperature forecast tonight to see if this remains on track or
if temps will need to be lowered some towards the deterministic
NBM.

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 107 PM PST Sat Jan 11 2025

An upper level digs to the south and then west, placing it over west
of southern California  early in the week. THen, upper level ridging
noses towards the PacNW midweek pushing that low pressure to the
south some more. Dry weather and chilly mornings are forecast for
the extended portion of the forecast. This matches well with the
Climate Prediction Center`s 6-10 day forecast which depicts likely
below normal temperatures and below normal chances for rain.

&&

.AVIATION...
(00Z TAFS)
Issued at 339 PM PST Sat Jan 11 2025

VFR with the exception of the North Bay where IFR conditions and
patchy fog may develop overnight. Gusty northerly winds will
continue into the evening before weakening, in places becoming
variable, overnight. The SFO-WMC gradient is expected to strengthen
(becoming more negative) through the day again tomorrow with
offshore flow to continue for most sites through the TAF period.
Confidence is low to moderate on fog development at STS with winds
expected to be light over night but RH values will generally be
between 60-70% (WRF model). LAMP guidance suggests that fog will
become more likely after 13Z and less likely after 18Z.

Vicinity of SFO...VFR through the TAF period. Gusty northerly winds
will weaken by the early evening hours with more moderate northerly
winds to continue through tomorrow afternoon. Winds will start to
shift more northwesterly at the end of the TAF period but stronger
offshore winds are expected to return by Monday as the SFO-WMC
gradient becomes more strongly negative.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals...VFR. Moderate northwesterly winds continue
through the evening. Winds become lighter and more variable
overnight, leaning more offshore, before moderate northwest winds
return during the day.
&&

.MARINE...
(Tonight through next Thursday)
Issued at 339 PM PST Sat Jan 11 2025

Expect strong and gusty northerly winds to continue through
Saturday night and early Sunday, especially over the outer waters.
Wave heights build to 10 to 15 feet and remain elevated through
the weekend, gradually subsiding through early next week. The
strongest winds will be located over the northern outer waters
where gale force gusts are likely through the weekend. Winds will
gradually ease early next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory from 6 AM to noon PST Sunday for CAZ006-
     506-508.

     Wind Advisory until 10 AM PST Sunday for CAZ504-512-514-515.

     Frost Advisory from 1 AM to 9 AM PST Sunday for CAZ516-518.

PZ...Gale Warning until 9 PM PST this evening for SF Bay N of Bay
     Bridge.

     Small Craft Advisory until 9 AM PST Sunday for Pigeon Pt to Pt
     Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Reyes to
     Pigeon Pt 0-10 nm.

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

     Gale Warning until 3 PM PST Sunday for Pt Arena to Pt Reyes 10-
     60 NM.

     Small Craft Advisory until 3 AM PST Monday for Pigeon Pt to Pt
     Pinos 10-60 NM.

&&

$$

SHORT TERM...KR
LONG TERM....KR
AVIATION...Kennedy
MARINE...RGass

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