FXUS66 KMTR 291943
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1243 PM PDT Sat Aug 29 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 1240 PM PDT Sat Aug 29 2026
- Cooling trend continues through at least midweek
&&
.SHORT TERM...
Issued at 1240 PM PDT Sat Aug 29 2026
(This evening through Sunday night)
Mostly sunny sky conditions have return to the region this
afternoon. This will lead to warmer conditions today over the North
Bay with the lack of mid/upper level high clouds. However,
temperatures across the region with be a few to several degrees
below normal as an mid/upper level low pressure system moves into
the Pacific Northwest and British Columbia.
The marine layer is forecast to deepen through the weekend. However,
with clearing skies off of the North Bay coast this afternoon, less
confidence for a return of stratus/fog overnight and into Sunday
morning. Still anticipate at least a patchwork of stratus/fog to
develop late this evening and moreso into Sunday morning along the
coast and into the adjacent valleys. For Sunday, expecting more of
the same as troughing persist along the West Coast.
&&
.LONG TERM...
Issued at 1240 PM PDT Sat Aug 29 2026
(Monday through next Friday)
A reinforcing trough develops and begins to deepen off of the
Pacific Northwest coast through the middle of the upcoming week. As
a result, afternoon temperatures will be some 5 to 15 degrees below
normal for this time of year. This will system will likely bring
rainfall to the Pacific Northwest. By late week, the NBM is
suggesting a better chance of rain/rain showers as the trough off of
the West Coast continues to deepen and potential drags a weak
frontal boundary across the region. There is still low to
moderate confidence of this occuring.
&&
.AVIATION...
(18Z TAFS)
Issued at 1151 AM PDT Sat Aug 29 2026
VFR prevails this afternoon as moderate onshore winds increase with
a few sites experiencing strong gusts around 20 kt in the late
afternoon. Onshore winds become gentle through the evening into the
overnight hours. The OAK 12Z sounding from this morning measured the
marine layer at a depth of ~1400 ft. An upper level low situated
over our area is expected to deepen the marine layer further. A mix
of IFR to low-end MVFR ceilings return tonight across the terminals
with medium confidence on arrival times and ceiling heights.
Vicinity of SFO...Northwest to westerly moderate winds prevail into
the evening with frequent strong gusts around 20 to 25 kt at SFO.
OAK may experience occasional 20 kt gusts during the afternoon.
Winds ease after sunset into the overnight hours. Relied on
persistence from last night on stratus arrival with medium
confidence for MVFR ceilings. Some model guidance hinted at the
possibility for IFR ceilings similar to last night, but given the
expected deepening of the marine layer, the TAF advertises low-end
MVFR.
SFO Bridge Approach...Occasional strong gusts through the afternoon.
Cloud cover may be patchy overnight, depending on how well organized
the marine layer becomes. Otherwise, similar to SFO.
Monterey Bay Terminals...VFR through the afternoon with an early
arrival of IFR ceilings around sunset for MRY and after sunset for
SNS. Moderate onshore winds prevail through the day and diminish to
gentle overnight.
&&
.MARINE...
(Today through Thursday)
Issued at 914 AM PDT Sat Aug 29 2026
Northwest winds remain fresh with strong to near gale force gusts
today into Sunday night. In response, wind driven seas build to
rough this afternoon and steadily subside to moderate through next
week. A long period southerly swell also peaks today around 17 to
18 seconds and gradually diminishes by Sunday night.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Sunday for Mry Bay-Pigeon Pt
to Pt Pinos 0-10 nm.
Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt
Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.
Small Craft Advisory until 9 PM PDT Sunday for Pigeon Pt to Pt
Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Navarrete
MARINE...Navarrete
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Prepared by Boulder-Creek.com Weather at: Sat Aug 29 14:30:02 PDT 2026
From the National Weather Service
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