FXUS66 KMTR 120532 CCA
AFDMTR
Area Forecast Discussion...CORRECTED
National Weather Service San Francisco CA
1032 PM PDT Fri Sep 11 2026
...New SHORT TERM, LONG TERM, AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1017 PM PDT Fri Sep 11 2026
- Breezy onshore winds Saturday afternoon through Sunday morning
- Temperatures near seasonal averages through the next week
&&
.SHORT TERM...
Issued at 1017 PM PDT Fri Sep 11 2026
(Tonight through Saturday night)
Satellite imagery reveals something pretty peculiar for this time of
year, so soon after the marine layer redeveloped after a couple days
of heat: clear skies across most of the Bay Area and Central Coast,
as a weak frontal boundary helped to scour out the marine layer
clouds over the afternoon and evening hours. Observations from the
Bodega Bay profiler suggest that the marine layer itself is still
there, hovering around 1000-1500 feet, so it remains to be seen if
any of the remaining stratus, most notably the patch on the eastern
side of Monterey Bay, can linger through the night, and whether any
new stratus can form overnight. Looking at the high resolution
output, it doesn't seem likely and many of us may see the skies
remain clear overnight.
A strong cutoff low hovers off the coast of the Pacific Northwest,
helping contribute to the cooling trend that started Thursday night
and continued through the following day. Through Saturday the cutoff
low is expected to inch its way into the state of Oregon, helping to
tighten the local pressure gradient and building breezy and strong
onshore winds in the afternoon and evening hours on Saturday before
winds ease Sunday morning. Wind gusts will generally reach 25 to 35
miles per hour, with favored gaps, passes, valleys, and coastal
areas seeing gusts to 45 miles per hour.
Morning lows will hover in the middle 50s to lower 60s for the lower
elevations, and into the middle 60s for the higher elevations.
Afternoon highs range from the upper 70s to middle 80s for the
inland valleys, up to the 90s in the warmest spots of the far
interior Central Coast, the upper 60s to the middle 70s close to the
Bays, and the lower to middle 60s along the Pacific coast.
&&
.LONG TERM...
Issued at 1017 PM PDT Fri Sep 11 2026
(Sunday through next Friday)
The trough axis continues moving eastwards Sunday into the early
part of next week, helping to relax the pressure gradient and lower
the wind gusts for Sunday. Despite the trough axis moving into the
northern Rockies and Plains, some troughing influence will remain
across the West Coast, keeping temperatures near to slightly below
seasonal averages. The pattern will remain remarkably stable through
the remainder of the 7-day outlook. Highs will range from the middle
70s to the middle 80s inland, the upper 60s into the 70s close to
the Bays, and the lower to middle 60s along the Pacific coast. Low
clouds will likely develop overnight into the morning, while breezy
onshore winds will set up in the afternoon and evening hours. Longer-
term outlooks suggest a lean towards temperatures above seasonal
averages and precipitation totals near to above seasonal averages
towards the latter part of September.
&&
.AVIATION...
(06Z TAFS)
Issued at 1017 PM PDT Fri Sep 11 2026
Much of the region has cleared out through the afternoon and evening
hours with a lingering patch of stratus on the east side of Monterey
Bay slowly diminishing over the last hour. Confidence in stratus
development away from the immediate coast has dropped and would
depend on radiational cooling overnight, making the situation
difficult to forecast. Highest confidence in stratus development
lies on the western side of the San Mateo Peninsula near HAF, the
Monterey Bay region, and to a lesser extent, the plain around STS
where scattered high clouds may complicate the radiational cooling.
Otherwise VFR through the night, with light to gentle winds into
Saturday morning. Moderate winds with strong gusts will develop
Saturday afternoon. Low confidence in wind speeds and stratus
development beginning Saturday evening, as strong winds aloft could
mix down and keep winds breezy and stratus at bay well into the
night.
Vicinity of SFO... Moderate to high confidence that VFR conditions
persist through the TAF period. Light to gentle northwest winds
persist overnight before strong and gusty winds come to the terminal
Saturday afternoon into the evening.
SFO Bridge Approach... Similar to SFO.
Monterey Bay Terminals... Low confidence in the stratus forecast for
the overnight period with a patch of stratus trying to hang on to
the north of the terminals. Considered VFR TAFs throughout but can't
rule out a burst of radiationally-driven clouds in the early morning
hours. Any stratus that does form clears out Saturday morning after
sunrise with breezy northwest winds developing in the afternoon
hours.
&&
.MARINE...
(Tonight through next Thursday)
Issued at 1017 PM PDT Fri Sep 11 2026
Hazardous conditions for small craft prevail late this weekend
through the middle of next week. A moderate to fresh northwest
breeze will continue to increase to a strong breeze by early
Sunday and continue into the early work week. Near gale force
gusts to occasional gale force gusts are expected along the inner
waters from Pigeon Point to Point Piedras Blancas, the Monterey
Bay, and in portions of the San Francisco and San Pablo Bays.
Moderate seas will build, becoming rough by Monday in response to
the stronger winds.
&&
.FIRE WEATHER...
Issued at 429 AM PDT Fri Sep 11 2026
A new weather pattern will influence conditions over the Timber
and Plaskett Fires in Monterey County. The marine layer has
returned and is 1,600 feet deep as measured by the 12Z balloon.
This height should be fairly consistent through the day before
some expansion this weekend as the trough moves through. While the
marine layer brings much cooler and more humid conditions to the
coast, areas above the marine layer often experience nocturnal
drying as the dry air above the clouds rolls in simultaneously
with the low clouds. In the late morning the clouds will mix out
as the layers become less stratified, often increasing dew point
during the warmest part of the day.
Flynn
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM Saturday to 9 AM PDT Sunday for
Pigeon Pt to Pt Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm-
SF Bay N of Bay Bridge.
Small Craft Advisory from 9 AM Saturday to 3 AM PDT Sunday for
Mry Bay.
Small Craft Advisory until 9 AM PDT Sunday for Pt Arena to Pt
Reyes 0-10 nm.
Small Craft Advisory until 9 PM PDT Saturday for Pt Pinos to Pt
Piedras Blancas 0-10 nm.
Gale Warning from 9 PM Saturday to 9 AM PDT Sunday for Pt Pinos
to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 AM PDT Saturday for Pt Arena to Pt
Reyes 10-60 NM.
Small Craft Advisory from 3 PM Saturday to 9 AM PDT Sunday for
Pigeon Pt to Pt Pinos 10-60 NM.
&&
$$
SHORT TERM...DialH
LONG TERM....DialH
AVIATION...DialH
MARINE...DialH
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Prepared by Boulder-Creek.com Weather at: Sat Sep 12 00:30:03 PDT 2026
From the National Weather Service
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