FXUS66 KMTR 251111
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
411 AM PDT Thu Jun 25 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Issued at 1200 AM PDT Thu Jun 25 2026
- Continued mild and dry for Thursday with winds increasing through
the day
- An upper trough brings cooler temperatures, moisture, and a
deeper marine layer for Friday and Saturday
- Gusty onshore winds continue to increase, peaking Friday and
Saturday, with mountain passes gusting as high as 50-60 mph and
marine concerns through the weekend
&&
.SHORT TERM...
Issued at 1200 AM PDT Thu Jun 25 2026
(This morning through Friday night)
The marine layer continues to slowly compress into this morning
to around 800-1200ft, with slightly less stratus inundation
expected. Patchy fog again is possible along the coastal terrain.
Upper-level troughing will begin to push in today, with heights
slowly falling. Temperatures overall will be fairly similar to
Wednesday, maybe 1 to 3 degrees cooler due to the decreasing
heights. A more significant cooldown will arrive Friday as
heights continue to fall with the approaching low to the north.
While the low stratus will dissipate, an increase in mid to high
level clouds is expected through the end of the workweek as
moisture increase with the upper-level trough deepening over the
West Coast as a large upper-level low sweeps down the Canadian
coastline.
Gusty onshore winds could begin as early as this afternoon,
increasing through the night. A frontal passage Friday could bring
about 40-50+ mph winds for mountain passes and wind-prone spots, and
30-35 mph winds for the coastal waters. Low and mid-level moisture
will surge in Friday as well, with a deepening marine layer and 50%+
min RH for every location except the very far interior spots. As a
result, fire weather concerns will be limited with excellent
overnight recovery into Saturday morning. Spotty drizzle and light
rain are possible, although, little to no rain accumulation expected.
The long-period southerly swell impacting the Pacific Coast beaches
continues to slowly subside. While the risk for sneaker waves and
strong rip currents has decreased, they could still occur...never
turn your back to the ocean. The southerly swell is expected to
subside through the end of work week before increasing again by the
weekend.
&&
.LONG TERM...
Issued at 1200 AM PDT Thu Jun 25 2026
(Saturday through next Wednesday)
The cooler pattern with gusty onshore winds continue into the
weekend, with ample moisture and deep marine layer limiting heating.
Saturday will be the coolest day of the period and highs will be
about 2 to 4 degrees cooler than Friday, with 50s near the coast and
60s to low 70s further inland. Again, spotty drizzle and rain is
possible.
While troughing pattern is looking to linger longer over the western
US, a slight warming trend is expected to begin on Sunday and
continue into next week as the the upper low departs and heights
increase slowly. Ensemble members continue to trend more in favor
with a troughing pattern prevailing into early week which would
support a minimal to slow warming trend compared to the cooler
weekend. Lingering breezy winds on Sunday will also trend down
into next week as the gradient relaxes.
&&
.AVIATION...
(12Z TAFS)
Issued at 410 AM PDT Thu Jun 25 2026
Extensive MVFR-IFR stratus has developed across the region, with
patches of LIFR stratus near STS. Stratus will retreat to the
immediate coast through the morning, with moderate onshore breezes
gusting to 20-25 kt in the afternoon and evening hours. Stratus will
redevelop across the Bay Area and Central Coast valleys late tonight
into Friday morning, while the North Bay valleys remain VFR as
locally downsloping flow precludes the development of stratus.
Beyond the TAF period, a passing trough should lead to delayed
clearing times Friday morning and gustier winds Friday into
Saturday.
Vicinity of SFO... MVFR-IFR stratus persists into the late morning
hours with strong west-northwest winds gusting to 25 to 30 kt
developing this afternoon and evening. Moderate confidence in the
timing of the incoming stratus tonight, but ceilings should develop
by the early morning hours on Friday and not clear out through the
remainder of the TAF period.
SFO Bridge Approach... Similar to SFO.
Vicinity of OAK and SJC... MVFR-IFR stratus continues at the
terminals into the late morning hours. Moderate to fresh northwest
winds will develop at the terminals this afternoon and evening, and
remain breezy overnight. Stratus should develop at both terminals
late tonight into early Friday morning, in SJC's case this will fall
near or slightly after the end of the 24-hour TAF period. Beyond the
TAF period, OAK might not clear out at all on Friday as a passing
trough and gustier winds promote stratus flow through the Golden
Gate.
Monterey Bay Terminals... MVFR stratus persists at the terminals
through the late morning hours when stratus retreats to the
immediate coast. Moderate northwest winds gusting to 15 to 20 kt
will develop in the afternoon and evening, with stratus decks
returning to the terminals early tonight.
&&
.MARINE...
(Today through Tuesday)
Issued at 410 AM PDT Thu Jun 25 2026
Fresh to strong breezes and rough seas will build through the day
through the weekend. Occasional gale-force gusts will develop
along the coastal waters north of Point Reyes. Hazardous
conditions for small crafts will develop tonight and continue
through at least early Friday before resuming over the weekend.
Long period southwest swell will persist through the extended
forecast.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 3 AM PDT
Saturday for SF Bay N of Bay Bridge.
Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Friday
for Mry Bay.
Small Craft Advisory from 9 AM Friday to 3 AM PDT Saturday for
Mry Bay.
Small Craft Advisory from 9 AM this morning to 3 AM PDT Saturday
for Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 3 PM this afternoon to 9 AM PDT Friday
for Pigeon Pt to Pt Pinos 10-60 NM-Pt Reyes to Pigeon Pt 0-
10 nm.
Small Craft Advisory from 9 AM to 9 PM PDT Friday for Pigeon Pt
to Pt Pinos 0-10 nm.
Small Craft Advisory from 9 PM this evening to 3 AM PDT Saturday
for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 AM PDT Friday for Pt Arena to Pt
Reyes 10-60 NM.
&&
$$
SHORT TERM...DS
LONG TERM....DS
AVIATION...DialH
MARINE...DialH
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Prepared by Boulder-Creek.com Weather at: Thu Jun 25 08:30:03 PDT 2026
From the National Weather Service
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