718
FXUS66 KMTR 211713
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1013 AM PDT Sat Jun 21 2025

...New AVIATION...

.SYNOPSIS...
Issued at 400 AM PDT Sat Jun 21 2025

Elevated fire weather concerns continue through Sunday morning.
Otherwise quiet weather on tap after that with near normal
temperatures.

&&

.UPDATE...
Issued at 850 AM PDT Sat Jun 21 2025

Skies are generally clear on this first full day of astronomical
summer. The forecast remains on track with gusty winds and dry
afternoon humidities resulting in elevated fire weather threat for
the interior through the day into the early part of Sunday
morning.

DialH

&&

.SHORT TERM...
(Today and tonight)
Issued at 400 AM PDT Sat Jun 21 2025

The forecast remains on track with an upper level low tracking into
the Great Basin, deepening the larger upper level trough. Flow
will remain onshore with gusty winds picking back up by mid to
late morning. The pressure gradient looks to support another gusty
day with gusts peaking 25-35 mph, with gusts up to 40 mph, or
locally higher. for areas along the coast or at wind prone gaps
and passes. The forecast looks to remain dry, especially for areas
above the marine layer where recovery is expected to be poor. The
marine layer should be around 1500-2000ft. Given these conditions
and cured grasses and dried shrubbery, elevated fire weather
countdowns will continue.

&&

.LONG TERM...
(Sunday through Friday)
Issued at 400 AM PDT Sat Jun 21 2025

Saturday evening into Sunday morning, winds look to remain breezy
before beginning to ease. Upper level troughing looks hold, though a
perturbation forms causing the through to deepen a bit more over
Central CA. This then looks to essentially park itself over CA and
NV through midweek with more zonal flow returning mid to late week.
Weather should generally be more typical for this time of year,
seasonable temperatures, nighttime and morning stratus, and
generally quiet weather.

&&

.AVIATION...
(18Z TAFS)
Issued at 1012 AM PDT Sat Jun 21 2025

Generally VFR conditions continue through the day. Strong northwest
gusts develop this afternoon and continue through early Sunday
morning, before diminishing through Sunday morning past the end of
the 24-hour TAF period. Some high resolution model data has stratus
returning to the immediate coast tonight into Sunday morning, but
this is a low confidence forecast and the HAF and MRY TAFs remain
VFR throughout.

Vicinity of SFO... VFR through the TAF period. Strong northwest
gusts will develop later today, with moderate confidence that the
gusts reach 35 kt sometime today. Greatest probability for gusts
reaching 35 kt will be sometime between 22 and 03Z. Strong gusts
will abate overnight, before gusts around 25 kt develop Sunday
afternoon.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals... VFR through the day with strong northwest
gusts developing this afternoon. Winds diminish late this evening
through the overnight period with a low confidence for stratus at
MRY. Northwest winds will redevelop late Sunday morning and
afternoon.

&&

.MARINE...
(Today through Thursday)
Issued at 850 AM PDT Sat Jun 21 2025

Widespread hazardous marine conditions are expected over the
waters through early Sunday morning in the form of near-gale
northerly breezes, severe gale force gusts, and rough to very
rough seas. The bays will be more sheltered, but will still
experience fresh to strong northwesterly breezes. Winds will
subside on Sunday, with fresh to strong northwest gusts and
moderate to rough seas through the end of the next work week.

&&

.FIRE WEATHER...
Issued at 557 AM PDT Sat Jun 21 2025

Elevated to near critical fire weather conditions continue today
across the interior Central Coast, East Bay Hills, and interior
North Bay as another dry day with moderate to poor RH recovery is
expected for interior locations and areas of higher elevation,
especially for those above the marine layer. Winds will be breezy
to gusty as well, peaking around 35 to 45 mph, perhaps locally
higher at exposed elevations and wind prone gaps. Breezy to gusty
winds look to hold through Sunday morning, with winds gradually
easing throughout the day. There should be some improvement in
humidity as well, especially if the marine layer is able to
deepen. Widespread critical fire weather conditions are not
expected within the district today, although the fire weather
threat will increase once again for areas closer to the Central
Valley. The fire weather threat will continue to diminish Sunday
into the early part of next week with the gusty winds further
relaxing, although humidity values in the interior will be slow to
rise.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Sunday for Mry Bay-SF Bay N
     of Bay Bridge.

     Gale Warning until 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 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...KR
LONG TERM....KR
AVIATION...DialH
MARINE...DialH

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