FXUS66 KMTR 220440
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
938 PM PDT Fri Aug 21 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 308 PM PDT Fri Aug 21 2026
- Temperatures will be close to or below normal into the beginning
of next week
- Warm and dry conditions above 1000ft persist into the weekend
&&
.SHORT TERM...
Issued at 308 PM PDT Fri Aug 21 2026
(This evening through Saturday night)
The forecast is on repeat today. Satellite imagery shows high clouds
streaming overhead and the stratus a bit more dispersed along the
coast. Expect these conditions to continue this afternoon, with the
marine layer making a return later this evening and overnight.
Guidance shows the marine layer should be around 1000-1500ft across
our service area, which should lead to another night and morning of
cloudy skies for the majority of the valleys. Low clouds continue to
clear by mid to late morning, with a few high clouds potentially
lingering into Saturday. With stratus clearing potentially a bit
earlier and less high clouds, highs should be similar to Thursday,
perhaps a few degrees warmer.
&&
.LONG TERM...
Issued at 308 PM PDT Fri Aug 21 2026
(Sunday through next Thursday)
The extended forecast looks similar, as we remain caught in the
quasi-zonal to weak troughing while high pressure holds to the east.
Temperatures should cool a few degrees on Sunday and then moderate
into early next week. Models and ensembles show ridging trying to
build slightly to the west, which would lead to warming for mid to
late next week. Some caveats to what might happen will be the
Pacific. The Tropical Weather Outlook from the National Hurricane
Center shows three potential disturbances well south of Baja. Could
influence how the high behaves.
&&
.AVIATION...
(06Z TAFS)
Issued at 938 PM PDT Fri Aug 21 2026
VFR prevails except for patchy coastal stratus and fog /IFR/
along San Mateo County and Monterey County. Mid and high clouds,
including wildfire smoke over the north Central Coast, are moving
northeastward over the forecast area. An area of cooler near
surface air will arrive from the northwest tonight and Saturday
morning resulting in a return of stratus, fog /IFR-LIFR/ and
possibly a few patches of drizzle.
Vicinity of SFO...It's VFR except cooler surface air will arrive
overnight, this will support redevelopment of stratus /IFR/. VFR
returns 18z Saturday. West wind 10 to 15 knots tonight and Saturday
morning. West wind increasing to 20 to 28 knots Saturday afternoon
to mid Saturday evening.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Erosion of stratus is still taking place
to the northwest across the Monterey Bay however orographic upslope
cooling of air parcels upon arrival vicinity KMRY is occurring
supporting a scattered to broken stratus /MVFR-IFR/ ceiling. Stratus
/IFR/ is forecast to reach KSNS tonight and Saturday morning.
Wildfire smoke so far is aloft. A few patches of drizzle are
possible tonight and Saturday morning. Conditions improve to MVFR-
VFR late Saturday morning and afternoon. Stratus /IFR/ returns
Saturday evening. West to northwest winds 5 to 15 knots.
&&
.MARINE...
(Tonight through next Thursday)
Issued at 932 PM PDT Fri Aug 21 2026
Widespread moderate to fresh northwest breezes prevail through the
weekend with slight to moderate seas. Locally strong breezes with
occasional near gale force gusts are expected in the coastal jet
regions of Point Sur and Point Reyes. Hazardous conditions for
small crafts are expected this afternoon for the bay waters and
immediate coastal waters.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Sunday for Pt Arena to Pt
Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt
Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory from 2 PM Saturday to 3 AM PDT Sunday for
Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60
NM-Pt Arena to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...KR
LONG TERM....KR
AVIATION...Canepa
MARINE...Canepa
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Prepared by Boulder-Creek.com Weather at: Fri Aug 21 22:30:03 PDT 2026
From the National Weather Service
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