275
FXUS66 KMTR 292230
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
330 PM PDT Fri Aug 29 2025

...New FIRE WEATHER...

.KEY MESSAGES...
Updated at 1256 PM PDT Fri Aug 29 2025

 - Temperatures near seasonal averages today, warming for the
   weekend through the middle of next week

 - Elevated fire weather concerns across the interior mountains
   this weekend with low RH and moderate onshore winds in the
   afternoons

 - Hazardous coastal conditions Saturday through Monday night due
   to long period southerly swell

&&

.SHORT TERM...
Issued at 1256 PM PDT Fri Aug 29 2025
(This evening through Saturday)

Stratus has cleared inland with temperatures this afternoon forecast
to warm into the upper 80s to lower 90s across the interior and in
the higher elevations, upper 60s to lower 80s just inland away from
the coast, and 60s to lower 70s near the coast/bays. Breezy onshore
winds are forecast to develop this afternoon and continue into the
evening with gusts of 25 to 35 mph in the favored gaps and passes,
Salinas Valley, and along the coast and in higher elevations.

Tonight, temperatures will cool into the 50s for most urban areas,
lower 60s across the interior valleys, and the 70s to lower 80s in
the higher terrain. Low clouds are also forecast to return inland
early Saturday morning and will dissipate by late morning. This will
bring increased humidity to lower elevations overnight, yet dry
conditions prevail in the higher elevations.

For Saturday, temperatures will warm by a few degrees with
temperatures forecast to be in the low 90s to near 100 degrees F
across the interior and in the higher elevations, low 70s to mid 80s
just inland away from the coast, and upper 60s to mid 80s near the
coast/bays. These temperatures will be 5-15 degrees F above average
for this time of year. This will result in isolated to scattered
Moderate HeatRisk across interior areas.

&&

.LONG TERM...
Issued at 1256 PM PDT Fri Aug 29 2025
(Saturday night through next Thursday)

Temperatures will hold steady as far as maximum/minimum temperatures
go through the remainder of the weekend and into early next week. As
such, Moderate HeatRisk will persist through at least through mid-
week of the upcoming week. We will need to keep an eye on the need
for any Heat products as we move into the upcoming week.

From previous forecaster: "This level of heat will bring a risk of
heat-related illnesses to vulnerable populations, including
children, the elderly, pregnant women, and people who are working or
living outdoors without adequate shelter or hydration. Near the
coasts, a compressed marine layer should retain the ability to keep
temperatures from rising dramatically, but areas that will lose the
marine layer influence, including much of the Bay Area, could see
temperatures jump 5 to 10 degrees. The heat will also contribute to
some elevated fire weather conditions across the interior mountains.
More information is available in the FIRE WEATHER section."

&&

.AVIATION...
(18Z TAFS)
Issued at 1206 PM PDT Fri Aug 29 2025

Lower CIGS are eroding, leading to widespread VFR this afternoon.
Expect winds to increase and become moderate for the afternoon and
evening. These winds reduce in the evening and into the night as low
clouds build along the coast, affecting HAF. CIGs will begin to fill
on the east side of the SF Bay affecting OAK in the late evening.
CIGS spread farther inland into the night, reaching APC as well as
SJC and  the Monterey Bay terminals, in the late night. Moments of
MVFR CIGS look to affect SFO into early Saturday while moments of
fog and LIFR CIGs look to affect STS. CIGS begin to erode again in
the mid to late morning for Saturday and widespread VFR is expected
to return that afternoon.

Vicinity of SFO...VFR lasts into early Saturday. Breezy west winds
return this afternoon with gusts up to 20 kts and look to last into
the late evening before reducing. Low clouds begin to fill around
the SF Bay in the early night, but don`t look to fill over SFO. Some
moments inconsistent MVFR CIGs affect SFO in the early morning but
clear in the mid morning on Saturday.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR lasts into the evening. Expect light
winds around the Monterey Bay into the mid afternoon before more
moderate winds arrive. Winds reduce in the early evening and become
light into the night. IFR CIGs fill over the terminals into the late
night. These CIGS and light winds look to affect the area until the
late morning on Saturday before CIGs erode and moderate west winds
return.

&&

.MARINE...
(Today through Wednesday)
Issued at 907 AM PDT Fri Aug 29 2025

Expect increasing wave heights through the weekend with fresh to
strong wind gusts developing Friday afternoon and lasting through
the holiday weekend. The gusty winds and choppy seas will create
hazardous conditions across our coastal waters through the weekend
into the beginning of the next work week.

&&

.FIRE WEATHER...
Issued at 312 PM PDT Fri Aug 29 2025

Warming and drying trend under way into this weekend as high
pressure builds aloft. Marine layer compression has begun this
afternoon with some areas showing as low 800-900 feet. Daytime
humidities will still be moderate-to-high below this elevation.
However, elevations above about 1,000 feet will see RH in the
teens during the afternoons through the weekend and into next
week. While we aren`t anticipated any long-duration wind events,
we do expect breezy NW winds to develop each afternoon during
peak heating, especially favoring gaps and passes in the East Bay
interior mountains. The energy release component (ERC) of
available fuels is showing slightly above average (higher burn
potential) for most locations across the region, with the most
notable being the North Bay zones which are forecasted to be well
above average for this time of year. Also, a fun tidbit worth
noting; we are right around our climatological peak for fuel
energy release component. Learn more about ERCs at
https://gacc.nifc.gov/oscc/fuelsFireDanger.php

Behringer

&&

.BEACHES...
Issued at 125 PM PDT Fri Aug 29 2025

Long-period (15-18 seconds) south-southwest swell originating from
previous Tropical Storm Juliette will impact the coast Saturday
through Monday night, creating an elevated risk for sneaker waves,
rip currents, and rough surf. This will be especially so at
southwest facing beaches including but not limited to Stinson
Beach, Santa Cruz Boardwalk Beach and Twin Lakes Beach. The
potential exposure to the dangers will be enhanced by the Labor Day
holiday weekend as folks flock to the coast to escape the hot inland
temperatures across the interior.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement from late tonight through Monday evening
     for CAZ505-509-529.

PZ...Small Craft Advisory from 9 AM Saturday to 3 AM PDT Sunday for
     Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt
     to Pt Pinos 0-10 nm.

     Small Craft Advisory from 3 PM Saturday to 3 AM PDT Sunday for
     Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60
     NM-Pt Arena to Pt Reyes 10-60 NM.

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

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Murdock
MARINE...Murdock

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