FXUS66 KMTR 221144
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
444 AM PDT Thu Oct 22 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1202 AM PDT Thu Oct 22 2026
- Rain showers continue through this afternoon
- A warming and drying trend expected for the upcoming weekend into
early next week
&&
.SHORT TERM...
Issued at 1202 AM PDT Thu Oct 22 2026
(Today and tonight)
Primary concern in the short term remains rainfall from the upper
level low just offshore of the Central Coast into early this
morning. The window for a chance of low-top supercells and the
accompanying severe threat has closed with just light rain expected
for spots that see any rainfall over the next 24hrs or so. The slow
moving upper level system is still expected to produce anywhere from
0.10"-0.50" for most spots over the course of the day today, with
coastal areas assisted by upslope flow to see the highest totals.
The rainfall on the back side of the system should taper off entirely
by sunset tonight and drier conditions filling in amid subsidence on
the backside of the exiting wave.
&&
.LONG TERM...
Issued at 1202 AM PDT Thu Oct 22 2026
(Friday through Wednesday)
PWATs begin to drop more considerably later in the day and evening
Friday indicating further drying conditions and warmer temperatures
for the weekend into the beginning of next week. However, temperatures
for the weekend into the beginning of the work week will hover
right around normal for this time of year, with no big warmup
indicated under relatively low amplitude, progressive ridging
through the middle of next week when troughing begins to develop
well offshore.
&&
.AVIATION...
(12Z TAFS)
Issued at 433 AM PDT Thu Oct 22 2026
VFR with temporary drops in visibility and ceiling heights likely
as stronger showers move through the Bay Area and Central Coast.
More persistent MVFR conditions are expected at LVK this morning
where showers are more consistently training over the airport.
Showers are likely to continue through late this afternoon with
a low potential (10-15%) of thunderstorms this afternoon. This is
a more widespread risk compared to yesterday so we will need to
keep an eye on the radar/amend if needed this afternoon. Moderate
onshore winds are likely this afternoon with winds decreasing
tonight into tomorrow morning. Confidence is low on the cloud
cover forecast for tonight/tomorrow morning. Current thinking is
that MVFR CIGs will become more likely early tomorrow morning
after showers end and mid-level clouds start to clear out.
Vicinity of SFO...VFR. Scattered showers will continue to impact
SFO through this afternoon with a low potential for thunderstorms.
Expect temporary reductions in visibility/ceiling heights and
gusty winds if a stronger shower or thunderstorm moves over the
airport. Shower activity decreases by late this evening and
mid/upper level clouds will start to clear out. MVFR CIGs look
likely to develop overnight but confidence is low to moderate in
the current CIG forecast.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. Showers return by mid to late
morning and persist through the rest of the day. There is a low
potential for thunderstorms this afternoon/evening which may reach
MRY and SNS. Temporary reductions in visibility and ceiling
heights are possible if a stronger shower moves over the airports.
Shower activity prevails longer over the Central Coast than the
Bay Area so have kept vicinity showers in through the overnight
hours as guidance shows occasional showers continuing overnight.
&&
.MARINE...
(Today through Tuesday)
Issued at 433 AM PDT Thu Oct 22 2026
Showers and isolated thunderstorms continue through this afternoon
as the upper level low pushes inland by this evening. Expect
gusty, erratic winds if a thunderstorm or stronger shower is able
to develop. Marine thunderstorm chances peak early Thursday
morning with thunderstorm chances shifting over the inner
waters/over land during the afternoon. Moderate northerly breezes
gradually return today with strong to near gale force gusts
increasing across the outer waters Thursday through Saturday.
Moderate seas build, becoming rough to very rough across the
outer waters Friday into Saturday before abating Sunday into next
week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 PM this evening to 3 AM PDT Friday
for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory from 9 PM this evening to 9 AM PDT Friday
for Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 3 PM this afternoon to 3 PM PDT Friday
for Pt Arena to Pt Reyes 10-60 NM.
Small Craft Advisory from 9 PM this evening to 3 PM PDT Friday
for Pigeon Pt to Pt Pinos 10-60 NM.
&&
$$
SHORT TERM...JM
LONG TERM....JM
AVIATION...Kennedy
MARINE...Kennedy
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Prepared by Boulder-Creek.com Weather at: Thu Oct 22 06:30:02 PDT 2026
From the National Weather Service
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