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NWS Technical
Weather Discussion |
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FXUS66 KMTR 231830
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1130 AM PDT Thu Jul 23 2026
...New AVIATION...
.KEY MESSAGES...
Updated at 1234 PM PDT Wed Jul 22 2026
- Breezy onshore winds return late this week and into the
weekend
- Temperatures near seasonal averages throughout early next week
&&
.UPDATE...
Issued at 908 AM PDT Thu Jul 23 2026
The stratus pattern was more typical for this time of year and was
able to spread into the inland valleys overnight. However, dry air
aloft was able to disrupt the cloud deck across the Monterey Bay
region. We also had fog in places like Russian River Valley, Santa
Rosa, Half Moon Bay, Marina, and Monterey at times this morning.
However, conditions continue to improve across much of the region as
low clouds retreat back to the coast. No significant updates needed
to the ongoing forecast at this time. More on the Beach Hazards
Statement with the afternoon update.
RGass
&&
.SHORT TERM...
Issued at 1245 AM PDT Thu Jul 23 2026
(Today and tonight)
Patchy coastal low clouds are trying to redevelop early this
morning. Higher dewpoint air lingers, however areal low cloud
coverage will depend on the total amount of nocturnal radiative
cooling (improved since it's drier aloft) and near surface cool
air advection through morning. Putting the brakes on low cloud
development so far is the recent uptick in sea surface temperatures
with the loss of cold water upwelling due to the recent northward
moving remnant low center passing by to our west. The buoys show
sea surface temps in the upper 50s to lower 60s, about 3F to 8F
above July normals. However, northwest winds (and upwelling) will
resume in our coastal waters today and tonight.
High pressure aloft will continue to bring stable weather. Daytime
highs today will be in the 60s/70s coastside to the 70s/80 bayside
and 80s/90s inland including 90s/100 over the southern interior.
Lows in the 50s to lower 60s tonight.
&&
.LONG TERM...
Issued at 1245 AM PDT Thu Jul 23 2026
(Friday through Wednesday)
A gradual turn toward less humid conditions with a slight warming
trend inland develops through the weekend into next week. Onshore
breezes will prevail with night and morning coastal low clouds and
fog, possibly a few patches of light drizzle.
&&
.AVIATION...
(18Z TAFS)
Issued at 1129 AM PDT Thu Jul 23 2026
.AVIATION...
VFR everywhere except at HAF, SFO, and OAK where borderline MVFR-IFR
ceilings are lingering. HAF will remain mainly IFR through the TAF
period with low confidence on brief VFR-MVFR conditions around 23-
01Z Friday. Dry air in the upper levels will continue to compress
the marine layer as it returns again tonight with a depth around
1000 feet. Given the shallow marine layer, SJC and LVK will be
spared from impactful stratus this TAF period. Moderate onshore
winds increase through the day and diminish shortly after sunset.
Medium confidence on stratus arrival and ceilings tonight.
Vicinity of SFO...Currently IFR but will soon become VFR through the
afternoon. High confidence on moderate to fresh westerly breezes
(around 15-20 kt) dominating the TAF period. Medium confidence on
timing of stratus as it may arrive sometime between 08-11Z and
persist until 17-18Z Friday.
SFO Bridge Approach...Similar to SFO. MVFR stratus will arrive and
scatter out after SFO does.
Monterey Bay Terminals...VFR as onshore winds increase through the
afternoon up to 15 kt. IFR ceilings impact MRY first around 08Z
before filling in over SNS. High confidence for ceilings to be
borderline IFR-LIFR at MRY and high-end IFR at SNS. Both should
scatter out around 17-18Z Friday.
&&
.MARINE...
(Today through Tuesday)
Issued at 908 AM PDT Thu Jul 23 2026
Moderate to fresh NW winds persist with embedded strong gusts,
allowing wave heights to remain moderate through the weekend. A
long period southerly swell from Hurricane Fausto also continues
to build this weekend and persists into early next week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement from Saturday morning through Tuesday
afternoon for CAZ006-505-509-529-530.
PZ...Small Craft Advisory until 9 PM PDT Friday for Mry Bay.
Small Craft Advisory from 3 PM this afternoon to 3 PM PDT
Saturday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt
Reyes 0-10 nm.
Small Craft Advisory until 3 PM PDT Saturday for Pigeon Pt to Pt
Pinos 0-10 nm.
Small Craft Advisory until 3 PM PDT this afternoon for Pt Pinos
to Pt Piedras Blancas 0-10 nm.
Gale Warning from 3 PM this afternoon to 9 AM PDT Friday for Pt
Pinos to Pt Piedras Blancas 0-10 nm.
&&
$$
SHORT TERM...Canepa
LONG TERM....Canepa
AVIATION...Navarrete
MARINE...Navarrete
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Prepared by Boulder-Creek.com Weather at: Thu Jul 23 12:30:03 PDT 2026
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From the National Weather
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reserved Boulder-Creek.com. |
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Revised:
29 Mar 2008 09:53 -0800 GMT
(Pacific) |
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