342
FXUS66 KMTR 052306
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
406 PM PDT Sat Jul 5 2025

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 131 PM PDT Sat Jul 5 2025

 - Temperatures remain below seasonal averages into early next week.

 - Marine layer increases and expands farther inland for end of the
   weekend and continues into early next week.

 - Gradual pattern change which will bring a warming trend
   starting Wednesday.

&&

.SHORT TERM...
Issued at 131 PM PDT Sat Jul 5 2025
(This evening through Sunday)

Near zonal flow will give way to an upper level low that has formed
off the Northwest Coast of CA this afternoon. This will slowly slink
meander to the south and then look to hold off our coast through
Sunday. This will lead to seasonably cool temperatures continuing
and lead to a deepening marine layer. For now, mostly clear skies
are observed across much of the Bay Area and Central Coast with
stratus clinging to the San Francisco/San Mateo coasts. Stratus is
expected to fill back in later this evening and into tonight, and
should seep into coastal valleys by Sunday morning. The clouds
should retreat to the coast by late Sunday morning or early Sunday
afternoon.

&&

.SHORT TERM...
Issued at 131 PM PDT Sat Jul 5 2025
(This evening through Sunday)

Near zonal flow will give way to an upper level low that has formed
off the Northwest Coast of CA this afternoon. This will slowly slink
meander to the south and then look to hold off our coast through
Sunday. This will lead to seasonably cool temperatures continuing
and lead to a deepening marine layer. For now, mostly clear skies
are observed across much of the Bay Area and Central Coast with
stratus clinging to the San Francisco/San Mateo coasts. Stratus is
expected to fill back in later this evening and into tonight, and
should seep into coastal valleys by Sunday morning. The clouds
should retreat to the coast by late Sunday morning or early Sunday
afternoon.

&&

.LONG TERM...
Issued at 131 PM PDT Sat Jul 5 2025
(Sunday night through next Friday)

A closed low should sit off just to our west through the early
portion of the work week, which will allow the marine layer to
deepen. Look for nighttime and morning clouds through midweek, with
perhaps some coastal drizzle Monday night and again Tuesday night. A
pattern change will start around Wednesday which is when ensemble
and cluster analysis show the ridge over the Desert Southwest
strengthening. Temperatures should increase for the later portion of
the week, with Thursday and Friday looking to be the warmest at this
time. It`s still too early to say how warm we`ll get as this time,
especially since models struggle with how strong the ridge will get.

&&

.AVIATION...
(00Z TAFS)
Issued at 404 PM PDT Sat Jul 5 2025

Currently VFR at all terminals with stratus off the coast. The
marine layer is currently being observed at 1,200 feet on the Fort
Ord profiler. A cutoff low off the coast will promote onshore winds,
the deepening of the marine layer, and coastal drizzle. Moderate to
high confidence on all terminals deteriorating below VFR tonight -
likely low-end MVFR to IFR ceilings for all but the coastal
terminals of HAF, MRY, and SNS which are expected to have LIFR
ceilings - with confidence lowering the farther inland the terminal
is. Widespread VFR is likely by tomorrow afternoon (with the
exception of HAF which will likely remain MVFR) with stratus
sticking close to the coast.

Vicinity of SFO...Currently VFR with westerly flow. High confidence
in sub-VFR ceilings returning to the terminal tonight with both
HREF and NBM giving a 90% chance - the ceiling will likely be low-
end MVFR to IFR. High confidence in VFR prevailing by tomorrow
afternoon. Westerly winds will prevail through the TAF period.

SFO Bridge Approach...Low clouds will begin to filter in to the San
Mateo Bridge Approach by 00Z with high confidence in them clearing
by tomorrow afternoon.

Monterey Bay Terminals...Currently VFR with westerly flow at both
terminals. High confidence in the return of sub-VFR ceilings to the
terminals tonight with both of them ultimately degrading to LIFR.
Brief VFR is expected tomorrow afternoon with stratus sticking close
to the coast. Westerly winds will prevail through the TAF period.

&&

.MARINE...
(Tonight through next Thursday)
Issued at 404 PM PDT Sat Jul 5 2025

Moderate seas and a fresh to strong northwesterly breeze will
continue through early Sunday. Winds will continue to ease on
Sunday  to a moderate to fresh breeze and then become southerly
while  diminishing into Monday. Northwesterly winds increase and
significant wave heights build beginning late in the upcoming
week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay-
     Pigeon Pt to Pt Pinos 0-10 nm.

     Small Craft Advisory until 9 AM PDT Sunday for Pigeon Pt to Pt
     Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

     Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

SHORT TERM...KR
LONG TERM....KR
AVIATION...Sarment
MARINE...RGass

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