941
FXUS66 KMTR 021628 AAA
AFDMTR

Area Forecast Discussion...UPDATED
National Weather Service San Francisco CA
928 AM PDT Mon Jun 2 2025

...New UPDATE...

.SYNOPSIS...
Issued at 332 AM PDT Mon Jun 2 2025

Near or slightly below normal temperatures will continue this week
along with continued dry weather. Highs mainly 60s along the coast,
70s bayside and 80s well inland. Night and morning low clouds
followed by afternoon and evening clearing near the coast.
Next inland warming trend may occur by next weekend.

&&

.UPDATE...
Issued at 921 AM PDT Mon Jun 2 2025

The inherited forecast is in good shape with just a few minor
tweaks to the sky and wind grids. An upper low will continue to
sink southward through the day today. As we`re already seeing with
our profiler network, winds aloft are becoming more offshore.
While most sites don`t see a reflection of the offshore winds at
the surface, the marine stratus continues to erode this morning.
With daytime heating, the afternoon seabreeze should kick in.
There is a noticeable Delta Breeze evident in most of the short-
term hi-resolution guidance and I`ve refreshed the grids to
reflect this. Wind/wind gusts this afternoon/evening across areas
of the west Delta (northern Contra Costa/southern Napa counties)
have been increased to 20 to 25 mph with gusts as high as 30 mph.

Also, the potential for convection across southern Monterey and
San Benito counties continues to wane. With the upper low being a
little farther to the west than initially thought, moisture
trajectories don`t appear quite as favorable for storms across our
area (better risk is farther south and east). Still, the chance
for pockets of CU to mature into TCU/CB later today and really on
Tuesday are non-zero across the interior Central Coast and we`ll
keep monitor of this potential.

&&

.SHORT TERM...
(Today and tonight)
Issued at 332 AM PDT Mon Jun 2 2025

Key Messages:

-Nighttime and morning stratus and fog.
-Near or slightly below normal temperatures.

Water vapor imagery this morning shows the upper low traversing down
the coast of CA. Minimal high cloud is being observed; however, if
you look at the nighttime microphysics and fog difference you can
see the marine layer has made a triumphant return into the central
Coast and Bay Area. This reduced the chance or even obliterated,
especially here in Monterey, the chance to see the aurora last
night or this morning. For areas where the stratus hasn`t
infiltrated, hopefully you got a chance to try and see the beauty
of the northern lights over the last two days.

In terms of today`s forecast, the low is expected to slide down
the coast while a closed low moves into the desert southwest.
Winds will shift to the south or southeast this morning and help
eradicate the stratus. Temperatures should remain seasonably cool
today, with stratus returning late tonight.

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 332 AM PDT Mon Jun 2 2025

Key Messages:

-Marine layer returns, with night and morning clouds each day.
-Near to slightly below normal temperatures through much of the
 week.
-Temperatures increase next weekend.

The closed upper level low from Monday should be west of southern CA
by Tuesday morning and begin pushing inland throughout the day. Some
guidance shows a ribbon of moisture trying to advect into central
and northern CA, along with some instability. The best chance to
see both of these ingredients is over southern Monterey and San
Benito counties; however, not many models are biting on to this.
We`ll likely be under either weak troughing to zonal flow at this
time, which should inhibit any thunderstorm development. We might
see some cumulus pop up over the ridges Tuesday afternoon while
the best chances for thunderstorms remain over the southern Sierra
or perhaps southern CA.

Beyond that, look for the June Gloom of nighttime and morning
stratus through the week and near normal to slightly below normal
temperatures. A warming trend, especially for interior locations,
looks likely for the weekend.

&&

.AVIATION...
(12Z TAFS)
Issued at 510 AM PDT Mon Jun 2 2025

Widespread MVFR CIGs across Bay Area and Central Coast with CIGs to
persist through mid to late morning. Highest confidence in CIGs
clearing between 15-17Z but there is some potential for CIGs to
persist through 18Z. Winds generally transition from more southerly
to west-northwesterly through the TAF period. Widespread gusts
between 20 to 25 knots are possible this afternoon before winds ease
overnight. Guidance is in agreement that stratus will return tonight
but there is still some variation in timing. For now, went with an
earlier arrival time for coastal sites and a later arrival for sites
across the interior.

Vicinity of SFO...MVFR CIGs are building in over the SF Bay and
impacting SFO. CIGs are expected to persist through at least 15Z
with a low to moderate (30-40%) chance of stratus persisting through
18Z. Gusty onshore winds are expected this afternoon into the
evening with gusts up to 25 knots possible. Winds ease overnight
with MVFR CIGs returning around 09Z.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR CIGs are expected to persist for much
of the morning with moderate confidence in clearing by 18Z. VFR
conditions will persist for much of the afternoon with MVFR CIGs set
to return early tomorrow evening. Highest confidence in CIGs
returning between 04-06Z but LAMP probability guidance does indicate
some potential for MVFR CIGs to return as early as 02Z. CIGs look to
gradually lower overnight with IFR CIGs becoming more likely after
09Z. Moderate onshore winds persist through this evening before
lighter, more variable winds develop overnight.

&&

.MARINE...
(Today through Saturday)
Issued at 911 AM PDT Mon Jun 2 2025

Rough seas and significant wave heights of up to 20 ft continue
across the northern outer waters and up to 15 ft across the
southern outer waters through early Monday afternoon. Winds
gradually ease by Tuesday but seas will remain rough with elevated
significant wave heights between 10 to 16 ft continuing late
Monday through mid to late week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Wednesday for Pt Arena to Pt
     Reyes 10-60 NM.

     Small Craft Advisory until 9 AM PDT Tuesday for Pigeon Pt to Pt
     Pinos 10-60 NM.

&&

$$

UPDATE...Bain
SHORT TERM...KR
LONG TERM....KR
AVIATION...Kennedy
MARINE...Murdock

Visit us at www.weather.gov/sanfrancisco

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