883
FXUS66 KMTR 121259 AAA
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
437 AM PDT Thu Jun 12 2025

...New SYNOPSIS, SHORT TERM, LONG TERM, AVIATION, MARINE...

.SYNOPSIS...
Issued at 252 AM PDT Thu Jun 12 2025

The daily pattern of the return of marine layer clouds overnight
through the morning hours, some coastal drizzle, and breezy
afternoon onshore winds continues. Temperatures remain in the
upper 50s and into the 60s at the coast, the 70 to 80s for areas
more inland, and into the 90s for the far interior. Areas away
from the marine layer continue to experience dry conditions,
leading to some fire concerns as grasses and smaller plants
continue to cure.

&&

.SHORT TERM...
(Today and tonight)
Issued at 252 AM PDT Thu Jun 12 2025


For the 3rd night in a row there is a reduction in cloud cover
across much of the area. The marine layer is around 2000ft and there
is still a fair push of moisture inland from it, but the increased
expansion of the marine layer has decreased the concentration of the
moisture and made it slightly harder for cloud cover to form
overland. This is coupled with the fact that low cloud transport
over the marine environment is moving mostly north to south, and not
much is turning towards the coast itself, also reducing our cloud
cover.

Pockets of fog and some areas of drizzle will still be possible
along the San Mateo Coast and around the Monterey-Carmel-Pacific
Grove area with slight chances around the SF Bay into the early
morning.

The reduced cloud cover will result in the warming trend for the
slightly more inland areas to continue today, while the cloudier
immediate coast stays cool and the far interior stays roughly the
same(warm). Breezy to gusty winds are expected in the afternoon and
into the evening, especially right along the dividing line between
the cloudier to clearer environments.

Cloud cover builds earlier this evening than Thursday night, with a
better feed of cloud cover building in from the ocean than what
we`re seeing this morning.


&&

.LONG TERM...
(Friday through Wednesday)
Issued at 252 AM PDT Thu Jun 12 2025

I`m struggling to find much remarkable about the next few days as
the pattern remains fairly solid:

-Cloudy on the coast
-Breezy and some clearing for the afternoons
-Warm days for the cloudless
-Cool days for the cloudy

The only true variations in temperatures and wind are going to be
for the areas that are going to be on the edges of the cloud cover.
So, we`re having fun with microclimates and how short drives can
mean the difference between putting the heater on or the
air conditioning in the car!

The pattern does look to change into the next work week! Models have
been hinting at a trough pattern arriving sometime over the weekend
for some time, but the passage has been delayed more and more with
each update. This has been from a combo of momentum changes and a
some different angling on the jet stream. For now, it looks like the
trough will arrive on Monday, but there is still some potential for
an even more delayed arrival. The tough itself will increase onshore
flow and lead to widespread cooling, but only up to 5 degrees or so
for daily highs, and even less so for overnight temps.

Model agreement has improved on the post-trough passage
environment, offering some reductions in onshore flow, but not so
much going into ridging nor offshore flow. It will offer some slight
warming, but as of the current forecast, nothing drastic.

&&

.AVIATION...
(12Z TAFS)
Issued at 437 AM PDT Thu Jun 12 2025

Currently a mixed bag of VFR-MVFR at the terminals with perhaps some
light drizzle near the coast this morning. Widespread VFR is
expected by this afternoon with a similar forecast on tap for
tonight as the pattern largely remains unchanged. Low level wind
shear is anticipated this evening, particularly in the North Bay, as
the atmosphere decouples - generally expect light southwesterly
winds at the surface with strong northwesterly winds aloft.

Vicinity of SFO...Currently MVFR with westerly flow. Optimistic
forecast construction in both improvement to VFR by mid-morning and
lack of sub-VFR ceilings tonight. Westerly winds will prevail
through the TAF period with gusts up to 30 knots to be expected.

SFO Bridge Approach...Conditions will improve from south to north
along the San Mateo Bridge Approach with high confidence in clouds
lifting above FL040 by this afternoon with an early possibility of
17Z on the table. Low clouds will return by 07Z.

Monterey Bay Terminals...Currently MVFR with southwesterly flow at
MRY and MVFR with westerly flow at SNS. VFR will prevail by this
afternoon with a similar forecast on tap for this evening.

&&

.MARINE...
(Today through Tuesday)
Issued at 252 AM PDT Thu Jun 12 2025

Fresh to strong northwesterly breezes, near gale force gusts,  and
moderate to rough seas will prevail through Monday. Expect gale
force gusts to develop near the coastal jet regions of Point Reyes
and Point Sur during the afternoon and evening hours of today and
tomorrow.

&&

.FIRE WEATHER...
Issued at 252 AM PDT Wed Jun 12 2025

Areas not being reached by the marine layer continue to see dry
conditions. Higher elevations, particularly in the Santa Lucias
and in the Gabilan range, continue to see poor humidity retentions
and recoveries. In fact, some locations are hitting single digit
and lower teens for RH values. A few locations in the interior
North Bay are seeing breezy north to northeast winds and these
winds look to last into the morning which will increase drying in
these areas. Winds will remain breezy each afternoon/evening
through the Delta, and any inland gap or pass. The combination of
dry fine fuels (grasses), lower RH, breezy winds with gusts in the
20-40 mph will elevate fire weather concerns.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT early this morning for SF
     Bay N of Bay Bridge.

     Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this
     evening for Mry Bay.

     Small Craft Advisory from 9 AM to 9 PM PDT Friday for Mry Bay.

     Small Craft Advisory until 3 AM PDT Saturday for Pigeon Pt to Pt
     Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt
     Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt
     Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

&&

$$

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

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