055
FXUS66 KMTR 020941
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
241 AM PDT Wed Jul 2 2025

...New KEY MESSAGES, SHORT TERM, LONG TERM...

.KEY MESSAGES...
Updated at 212 AM PDT Wed Jul 2 2025

 - Night and morning low clouds clearing to the coast each
   afternoon remains.

 - Near normal temperatures with a slightly below normal
   temperatures Thu & Fri.

 - Breezy northwest winds Thursday afternoon and evening.

&&

.SHORT TERM...
Issued at 212 AM PDT Wed Jul 2 2025
(Today and tonight)

For a few days now we`ve been talking about a non-zero chance for
thunderstorms over the North Bay Tuesday evening into Wednesday
morning. So, how`s that playing out? Well, radar has been put into
surveillance mode as it`s not detecting any storms. Synoptically
speaking, we still have an upper low spinning overhead. Spokes of
moisture continue to rotate around the low with a few moisture
pockets traversing the North Bay. Satellite imagery even shows
some of the moisture. LAtest guidance still shows decent
instability and moisture. However, one change from yesterday to
today is the moisture and instability is overlapping with a higher
amount of CINH or inhibition. Additionally, flow aloft at jet
stream level is less divergent and more convergent. We`ll the
situation isn`t favorable for thunderstorms we`ll still be keeping
an eye on it.

Otherwise, marine layer is once again in control with profilers
putting the depth near 1200-1500 feet. Patchy drizzle and fog have
been added to the coastal regions this morning. Marine layer will
once again roll back to the coast by mid-morning with inland
sunshine. Temperatures will be seasonably cool. Marine layer will
move inland again tonight with another round of drizzle/fog.

&&

.LONG TERM...
Issued at 240 AM PDT Wed Jul 2 2025 (Thursday through Tuesday)

The former upper low is now a open wave by Thursday with its
sights on the Four Corners region. In its wake, another sharper
upper level trough takes aim at CA. While dry for the forecast
area, the trough will usher in slightly cooler temperatures and
much windier conditions on Thursday. Not strong enough for a wind
advisory, but gusts of 25-40 mph will be possible over the
waters, coastal areas, higher terrain, and inland gaps/passes.

For the upcoming holiday, expect seasonably cool conditions
remains with night/morning clouds with afternoon inland sunshine.

Broad upper level troughing remains Friday and into the weekend
making for a rinse and repeat forecast.

&&

.AVIATION...
(06Z TAFS)
Issued at 1054 PM PDT Tue Jul 1 2025

Satellite imagery shows that stratus is rolling in this evening
with ceilings in the LIFR to IFR range. There is high confidence
that the majority of the terminals will develop ceilings over the
next few hours, with the possible exception of SJC and likely
exception of LVK. Otherwise the ceilings are coming in lower than
expected, and there will likely be visibility restrictions and
even some coastal drizzle in the deep cloud layer through early
Wednesday morning. Brief clearing is expected mid-day Wednesday.

Vicinity of SFO...Clouds are encroaching on the terminal both
over the peninsula and eventually from the Bay. The exact timing
is still a little uncertain, but there is high confidence that the
clouds will close in over the next few hours. When they do, the
ceilings will likely be close to LIFR as seen in coastal
observations and terminal cameras. With some wind expected
overnight, there is only a 10% of the visibility falling below
5SM. Compared to the last 24 hours, the clearing will occur at a
similar time tomorrow morning (1630-1700Z), but the stratus may
return sooner in the afternoon.

SFO Bridge Approach...Ceilings should develop an hour or two
sooner over the approach than at the terminal.

Monterey Bay Terminals...The marine layer stratus has arrived at
both MRY and SNS with LIFR ceilings. The cloud bases are lower than
expected and the chance for early morning fog has increased,
especially for MRY. There is roughly a 50-50 chance that the
terminals will clear out tomorrow, but the ceilings should at least
lift to high IFR or low MVFR in the middle of the day.

&&

.MARINE...
(Tonight through next Monday)
Issued at 920 PM PDT Tue Jul 1 2025

A strong NW breeze and rough seas will continue through Thursday
before improving briefly improving late week. A low-amplitude long
period southerly swell will arrive Thursday and persist through
Friday.

&&

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

     Small Craft Advisory from 9 AM this morning to 3 PM PDT this
     afternoon for Pt Arena to Pt Reyes 0-10 nm.

     Gale Warning from 3 PM this afternoon to 3 AM PDT Thursday for
     Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 9 AM PDT
     Thursday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Reyes to
     Pigeon Pt 0-10 nm.

     Small Craft Advisory from 9 PM this evening to 9 AM PDT Thursday
     for Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Gale Warning until 3 AM PDT Thursday for Pt Arena to Pt Reyes 10-
     60 NM.

&&

$$

SHORT TERM...MM
LONG TERM....MM
AVIATION...Flynn
MARINE...Flynn

Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook, X, and YouTube at:
www.facebook.com/nwsbayarea
x.com/nwsbayarea
www.youtube.com/nwsbayarea