812
FXUS66 KMTR 101122
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
422 AM PDT Tue Jun 10 2025

...New AVIATION...

.SYNOPSIS...
Issued at 238 AM PDT Tue Jun 10 2025

A slight cooling trend starts today for the more interior areas
Otherwise expect a continuation the daily patter of marine layer
clouds each night and morning, some coastal drizzle, a few
pockets of fog, and breezy onshore winds each afternoon and
evening.

&&

.SHORT TERM...
(Today and tonight)
Issued at 238 AM PDT Tue Jun 10 2025

The overnight forecasting team did some extra polishing into the
short term forecast. The fog/drizzle/ and cloud cover forecast have
been finely tuned and adjusted as the marine layer continues to
dominate the coast and the slightly inland. Patches of fog will favor
the North Bay valleys as well as the coast through the late morning.
Brief moments of drizzle will also be possible along the immediate
coast and around the Monterey Bay. So fairly similar morning
conditions as the last few days, but the pattern does begin to
change today.

The slight ridge pattern is turning into a more zonal upper level
pattern.

What does that mean? I`m glad you asked.

It means the upper level environment will start moving to a more
direct west to east flow over the west coast, leading to more
onshore flow. It also means today will be cooler for the more
interior areas that haven`t been seeing those strong pushes of low
level clouds from the marine environment. Don`t expect it to be a
robust cool-down, as most of the interior areas are only seeing a
few degrees difference.

For areas along the coast and affected by the marine layer, don`t
expect much in the way of change. A cloudy morning, with some
clearing in the afternoon and then back to cloudy in the evening.
It`s very much the summer stratus pattern giving the "June Gloom."
The change to zonal flow will expand the marine layer, allowing it
to flow deeper inland, but looks to reduce the concentration of
moisture within the marine layer, allowing for some areas to see
cloud cover to clear sooner.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 238 AM PDT Tue Jun 10 2025

The upper-level pattern will continue to promote onshore flow well
into the long term forecast. This will continue the cooling trend
for the more interior areas, as well as the cloudy coastal and
valley conditions. A weak trough looks to move through the area over
the weekend, allowing the marine layer expansion to continue. This
will result in the cloud layer levels rising through weekend, and
less chances for fog. After that, the longer term models are
struggling to figure out what to do with the post-trough
environment. Some models are hinting at a quick transition into a
ridge pattern in the middle of the next work week, leading to
another warming trend, while others stay more zonal, which keeps our
current trend. This will be something worth checking back in as the
forecast continues to develop!

&&

.AVIATION...
(12Z TAFS)
Issued at 421 AM PDT Tue Jun 10 2025

Currently a mixed bag of LIFR-MVFR at the terminals. Conditions are
expected to deteriorate a little bit more before the sun rises as
maximum relative humidity potential is realized. A dry cold front
and a coastal trough will allow for some light drizzle across the
region this morning, particularly right along the coast. VFR is
expected at all terminals (with the exception of HAF) this afternoon
with stratus sticking to the coast, and thus able to make an early
return tonight. Moderate onshore winds will prevail through the TAF
period.

Vicinity of SFO...Currently IFR with westerly flow. Conditions will
improve through the morning, with VFR expected for most of the
afternoon and evening. Moderate westerly winds are expected through
the forecast period.

SFO Bridge Approach...IFR conditions will improve from south to
north along the San Mateo Bridge Approach with OAK likely to remain
under sub-VFR conditions longer than SFO.

Monterey Bay Terminals...Currently LIFR with westerly flow at both
terminals. Short-lived VFR is expected by the afternoon with stratus
sticking close to the coast and having an early return this evening.
Westerly winds will prevail through the TAF period.

&&

.MARINE...
(Today through Sunday)
Issued at 238 AM PDT Tue Jun 10 2025

Fresh to strong northwesterly breezes will prevail through the
forecast period with gale force gusts possible beginning Wednesday
afternoon along the coastal jet regions of Point Reyes and Point
Sur. Significant wave heights will be moderate today, building to
become rough tomorrow.

&&

.BEACHES...
Issued at 240 AM PDT Tue Jun 10 2025

A long period southerly swell lingers into the day bringing a
higher risk for rip current along beaches. Breaking waves about 5
to 7 feet, but strong currents and sneaker waves will be the
bigger hazard. Use caution near the water and never turn your back
on the ocean.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM this morning to 3 PM PDT
     Wednesday for SF Bay N of Bay Bridge.

     Small Craft Advisory from 9 AM this morning to 9 PM PDT this
     evening for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm.

     Small Craft Advisory from 9 AM to 3 PM PDT Wednesday for Mry Bay-
     Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory until 9 AM PDT this morning for Pt Arena to
     Pt Reyes 0-10 nm.

     Small Craft Advisory until 3 PM PDT Wednesday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 3 PM PDT
     Wednesday for Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...Murdock
LONG TERM....Murdock
AVIATION...Sarment
MARINE...Sarment

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