FXUS66 KMTR 071135
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
435 AM PDT Mon Sep 7 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1143 AM PDT Sun Sep 6 2026
- Hazardous conditions at Pacific Coast beaches through Monday
- Warming and drying trend Monday through Thursday with
widespread moderate to areas of major HeatRisk
&&
.SHORT TERM...
Issued at 1259 AM PDT Mon Sep 7 2026
(Today and tonight)
Satellite imagery shows an area of stratus redeveloping along the
San Mateo County coastline and some stratus development over the
East Bay. Coastal water temps remain a few degrees Fahrenheit
above normal, however recent northwest winds have either held sea
surface temps steady or slightly edged readings 1F lower in the
last 24 hours. Radiative cooling through daybreak, cooler surface
to near surface air arriving from the northwest and the eventual
strengthening of a lower level temperature inversion should help
with at least patchy to areas of stratus and fog development.
After morning coastal stratus and fog mix out, daytime highs will
warm to the 70s coastside and to the 80s and lower 90s inland.
Reminder: A Beach Hazards Statement continues from the coastal
North Bay to the Big Sur coast through Monday evening.
Also, minor coastal flooding is likely within a small window of
time of about 1 hour nearest high tide Labor Day (Tuesday and
Wednesday as well) for bayshore locations of Marin County. Impacts
will include minor flooding of the lowest lying areas directly
along the shoreline. At the San Francisco tidal gauge, high tide
is expected to be 0.5 ft above normal (up to 1.0 ft above MHHW)
at 9:00 PM 9/7. At this time we are messaging it here and will
include messaging in social media vs issuing a coastal flood
advisory for Monday.
&&
.LONG TERM...
Issued at 1259 AM PDT Mon Sep 7 2026
(Tuesday through Sunday)
Dry weather remains in the forecast. Will have to closely monitor
remnant mid to high level tropical clouds that may arrive here
during the week. Higher to much higher precipitable water (pw)
may arrive here during the week, with 1.40" pw reaching the Bay
Area according to the latest GFS model. This week's forecast of
hot temperatures is dependent on strengthening of 500 mb high
pressure (and compressional warming) as the current models show,
however some of this strength may be in response to what happens
to eventual post tropical remnants entraining into the upper low
over the east Pacific. There are also hints of cool air advection
returning on northwest winds late in the week. For now it's a low
confidence forecast as to timing, location (and duration) as to how
hot it may get here (closest to the coastline mainly) during mid-
week. Will monitor model output closely for now before decision
making on heat advisories. Stay tuned to the latest updates.
&&
.AVIATION...
(12Z TAFS)
Issued at 425 AM PDT Mon Sep 7 2026
Mostly clear skies across the region this morning with low clouds
reported at APC and HAF. Stratus will clear by late morning with
VFR through the rest of the day. Variable, lightly offshore winds
are expected this morning with winds less than 6 knots. Breezy
onshore winds return this afternoon/evening but will be weaker
than those observed yesterday. Low confidence that stratus will
return tonight given the marine layer struggling to
rebuild/remaining compressed below 500 ft.
Vicinity of SFO...VFR through the TAF period. Breezy onshore winds
to around 16 knots are expected this afternoon/evening before
winds ease overnight. Variable, lightly offshore winds are
possible this morning and again tomorrow morning.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR with a low potential for stratus to
expand into SNS temporarily this morning. Any clouds that do
develop along the Monterey Peninsula will clear by mid to late
morning with VFR through the rest of the TAF period. Stratus is
unlikely to impact MRY/SNS before 12Z tomorrow morning. Breezy
onshore winds during the afternoon/evening with light, offshore
winds overnight.
&&
.MARINE...
(Today through Saturday)
Issued at 425 AM PDT Mon Sep 7 2026
Moderate to fresh northwest breezes with strong gusts decrease
across the coastal waters today becoming more moderate. Northwest
winds gradually diminish to gentle to moderate by Monday night
which then prevails through the remainder of the week. Winds look
to increase late this week into the weekend. A long period
southerly swell induced by distant tropical cyclone activity in
the East Pacific prevails into next week.
&&
.BEACHES...
Issued at 1213 AM PDT Mon Sep 7 2026
A Beach Hazards Statement is in effect through Labor Day. Moderate
to long period swell will increase the chance for sneaker waves,
since there are 2 different sets of southerly swell, and their
energy will periodically combine. In addition to sneaker waves,
expect strong rip currents and breaking waves up to 10 ft. As this
is a holiday weekend and the weather is otherwise pretty nice,
the exposure to the risk is high. Avoid the water if you're not an
expert swimmer. If caught in a rip current, swim parallel to shore
until you stop feeling the pull. Even on the beach, be prepared
for sneaker waves this weekend and never turn your back on the
ocean.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through this evening for CAZ006-505-509-
529-530.
PZ...Small Craft Advisory until 9 AM PDT this morning for Pt Arena to
Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...Canepa
LONG TERM....Canepa
AVIATION...Kennedy
MARINE...Kennedy
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Prepared by Boulder-Creek.com Weather at: Mon Sep 7 08:30:02 PDT 2026
From the National Weather Service
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