070
FXUS66 KMTR 312124
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
224 PM PDT Thu Jul 31 2025

...New SHORT TERM, LONG TERM...

.KEY MESSAGES...
Updated at 201 PM PDT Thu Jul 31 2025

 - Coastal drizzle along areas of the coast each morning

 - Mild weather to continue through the forecast period

 - Gusty onshore winds out of the west-northwest Sunday and Monday

&&

.SHORT TERM...
Issued at 224 PM PDT Thu Jul 31 2025 (This evening through
Friday)

A stout marine layer remains in place over our service area. This
has been manifesting in low clouds each morning with clouds linger
along the coast through much of the day. For example, looking at
webcams around the region and the two coastal profilers, the
clouds have lifted off the surface in the southern part of the
coast while they firmly on the ground along the North Bay Pacific
coastline. This pattern will repeat itself Friday as well, as
there are no significant changes to the pattern coming in the next
24 hours. If you like today`s weather, you`re going to like
tomorrow.

&&

.LONG TERM...
Issued at 224 PM PDT Thu Jul 31 2025 (Friday night through next
Wednesday)

Aside from the simple pattern that`s effectively established, we
do have a boundary sliding across the area on Sunday. As stated
by my colleagues discussion this morning, "by Sunday, a more
potent trough out of the Gulf of Alaska is progged to move through
the northern half of the state resulting in increased moisture
and gusty onshore winds. A few discussions ago I had mentioned the
potential for offshore winds by the middle of next week. Updated
guidance has advertised a more favorable track for the upper low
which has shifted the focus to gusty ONshore winds earlier in the
period (Sunday and Monday). Most favored areas will be coastal and
high elevation areas, as well as NW/SE oriented gaps and passes.
There still does exist a low chance of breezy northerly winds
across the North Bay as the low translates inland early Tuesday.
However, this appears to be a fairly short period as winds revert
back to a more onshore component by Wednesday".

The models this afternoon have only reinforced this change in wind
strength coming for Sunday and Monday. Both the EC EFI and NAEFS
Standardized Anomalies have picked up on it. Therefore, Sunday and
Monday afternoon/evening look for gusty conditions along the
coast, coastal mountains and passes, as well as known windy spots
such as Altamont Pass. This is not an event that will rise to the
level of wind advisory, however, with the number of recreational
campers and fifth wheels, there is a concern for non-experienced
drivers loosing control in gusty conditions.

After we get through this brief hit of winds it will be back to
our doldrums summer.

&&

.AVIATION...
(18Z TAFS)
Issued at 1030 AM PDT Thu Jul 31 2025

Low stratus can be seen rapidly eroding on visible satellite
imagery late this morning with VFR expected for most terminals by
early afternoon. Expect breezy onshore flow this afternoon,
eventually easing late this evening. Once the low stratus retreats
to the coastline this afternoon, expect a return of MVFR/IFR
ceilings around sunset, persisting through the remainder of the
forecast period.

Vicinity of SFO...Similar to SFO.

SFO Bridge Approach...Expect VFR through the remainder of the
afternoon and early evening with IFR ceilings expected to return
around sunset tonight. High confidence in IFR ceilings persisting
through much of the remainder of the forecast period, with a
slight chance of LIFR ceilings.

Monterey Bay Terminals...Valley fog over KSNS is rapidly
retreating with VFR conditions imminent as of 11AM PDT. A steady
stream of coastal stratus will continue across KMRY into the early
afternoon. A return of IFR ceilings is expected around sunset
tonight, persisting through the remainder of the forecast period.
There is a slight chance of LIFR ceilings during the overnight
into the early morning hours on Friday.

&&

.MARINE...
(Today through Tuesday)
Issued at 254 AM PDT Thu Jul 31 2025

Fresh to strong northwesterly breezes will prevail with gale force
gusts developing in the coastal jet regions of Point Reyes and
Point Sur by Sunday afternoon. Moderate to rough seas will
prevail through Monday.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Saturday for Pt Arena to Pt
     Reyes 0-10 nm.

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

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

&&

$$

SHORT TERM...BFG
LONG TERM....BFG
AVIATION...JM
MARINE...JM

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