FXUS66 KMTR 251914
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1214 PM PDT Thu Jun 25 2026
...New AVIATION...
.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...
(18Z TAFS)
Issued at 1213 PM PDT Thu Jun 25 2026
Stratus is making its way out of most terminals this morning.
Widespread VFR conditions are expected by 19-20Z today, with the
exception of HAF where it'll remain borderline IFR-MVFR through the
TAF period. Moderate onshore winds increase through the afternoon
with gusts between 20-25 kts at most terminals. Winds remain
elevated overnight diminishing as low as 8-10 kts with the arrival
of the marine layer. Widespread MVFR-IFR ceilings are anticipated as
the stratus deck moves onshore and remains until 16-19Z. High
confidence on wind speeds and gusts. Medium confidence on exact
arrival of the stratus, especially at STS where they may be
intermittently MVFR-VFR.
Vicinity of SFO...VFR until about 07Z Friday when MVFR ceilings
begin to fill into the terminal. High confidence that moderate
westerly winds will increase by the afternoon with 25-30 kt gusts to
begin around 01Z Friday. Gusty conditions persist overnight and
diminish by 12Z Friday. MVFR ceilings may clear later tomorrow
morning and conditions will become VFR by 21Z Friday. Medium
confidence on exact timing of the stratus deck as they may roll in a
couple hours later.
SFO Bridge Approach...Same general wind pattern as SFO, though
moderate winds remain more NW-W with gusts up to 25kt. MVFR ceilings
(BKN015-020) may roll in a few hours later and scatter out earlier
than SFO.
Vicinity of OAK and SJC...Moderate winds (10-15 kt) increase by the
afternoon remaining from the west at OAK and NW at SJC. High
confidence that both sites will experience gusts around 20 kt during
the afternoon. MVFR ceilings roll in around 07Z Friday at OAK and
09Z Friday at SJC, though currently have medium confidence on the
timing of stratus.
Monterey Bay Terminals...VFR conditions prevail through the
afternoon with a higher chance for SNS to experience 20 kt gusts.
MVFR ceilings will impact MRY first around 23Z Thursday and then
approach SNS around 01Z Friday. Ceilings will remain on the
borderline of low end MVFR to high end IFR and may jump between the
two throughout the night. Both will see a clearing around 17Z Friday.
&&
.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 until 3 AM PDT Saturday for SF Bay N of Bay
Bridge.
Small Craft Advisory from 9 AM Friday to 3 AM PDT Saturday for
Mry Bay.
Small Craft Advisory until 3 AM PDT Saturday for Pt Arena to Pt
Reyes 0-10 nm.
Small Craft Advisory until 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...Navarrete
MARINE...DialH
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Prepared by Boulder-Creek.com Weather at: Thu Jun 25 12:30:03 PDT 2026
From the National Weather Service
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