FXUS66 KMTR 060440
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
940 PM PDT Sat Sep 5 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 111 PM PDT Sat Sep 5 2026
- Hazardous conditions at Pacific Coast beaches through Monday
- Below normal temperatures through the weekend, gradual warming
and drying trend kicks off Monday through Thursday
- Light rain showers from remnant tropical moisture possible
Tuesday through Friday
&&
.SHORT TERM...
Issued at 111 PM PDT Sat Sep 5 2026
(This evening through Sunday night)
Hazardous conditions at Pacific Coast beaches will be the main story
through Monday. Long period southerly swell from distant Hurricane
Marie will result in an increased risk for sneaker waves and strong
rip currents with breaking waves up to 10 feet. The ocean is not
your friend this weekend, so enjoy the unofficial end of summer
anywhere but the beach. Sensible weather wise, well below normal
temperatures and onshore flow will continue through Sunday. The
marine layer continues to be the lowest confidence aspect of the
short term forecast. The 12Z sounding found a temperature inversion
at 1,400 feet; however, boundary layer winds were not onshore and
thus clouds struggled to form. The normal marine layer may continue
to struggle to form through the weekend with little forcing in
place. As upper-level ridging nudges in from the east on Monday, a
gradual warming and drying trend will commence and the marine layer
is slated to return.
&&
.LONG TERM...
Issued at 111 PM PDT Sat Sep 5 2026
(Monday through next Friday)
Global ensemble clusters have come into much better agreement with
the long term forecast, especially Tuesday through Thursday. Upper-
level ridging will continue to build in from the east on Tuesday;
simultaneously, a cutoff low will dig well off the West Coast and
pickup what will likely be Post-Tropical Cyclone Marie. The farther
west track of the low and a stronger ridge has led to a warmer and
drier forecast. Even though we are now expected to be on the fringes
of it, the upper-level pattern will act as a conveyor belt for
remnant tropical moisture with cyclonic flow to the west and anti-
cyclonic flow to the east. Rainfall totals up to 0.10" can be
expected, favoring coastal and higher terrain locations.
Temperatures will moderate to near normal and climb up to 10 degrees
above normal by Thursday, introducing minor to moderate HeatRisk.
&&
.AVIATION...
(06Z TAFS)
Issued at 940 PM PDT Sat Sep 5 2026
Generally VFR conditions with patches of stratus developing at the
coast and along favored ridgelines through the night. Lower
confidence in the model output that puts stratus development at the
Monterey Bay, and to a lesser extent the North Bay valleys, through
the night. Stratus should mix out through Sunday morning with breezy
onshore winds resuming in the afternoon and evening hours.
Vicinity of SFO... Moderate to high confidence in VFR conditions
through the TAF period, with some MVFR clouds possible early Sunday
morning. Gentle northwest winds will continue through the night
before moderate westerly winds with strong gusts resume Sunday
afternoon and evening.
SFO Bridge Approach... Similar to SFO.
Monterey Bay Terminals... VFR at present. Model output continues to
show the possibility of stratus development across the region but it
hasn't been observed as of yet and the model output is overdoing the
stratus extent offshore. Thus, have elected to leave out mention of
ceilings through the night. Light winds continue through the
overnight period with a gentle to moderate northwest breeze
developing Sunday afternoon and evening. Low confidence in some
stratus developing Sunday night into Monday morning, particularly at
MRY.
&&
.MARINE...
(Tonight through next Friday)
Issued at 940 PM PDT Sat Sep 5 2026
Gentle to moderate northerly to northwesterly breezes continue
through the beginning of next week. Diurnal moderate to strong
breezes are expected across the San Pablo, San Francisco, and
Monterey Bays each afternoon and evening into the beginning of
next week. Fresh to strong gusts become more widespread early next
week before winds decrease by midweek. Long period southerly
swell will continue to impact the coastal waters through much of
the upcoming week.
&&
.BEACHES...
Issued at 538 PM PDT Sat Sep 5 2026
A Beach Hazards Statement is in effect through Labor Day as the
swell from tropical cyclones Marie and Karina reach the coast.
Waves from these cyclones will travel over 1,000 miles in all
directions, gradually flattening out to low amplitude, but long
period swell. These waves aren't very intimidating if you're on a
boat in the open ocean, but the long period allows them to push
much farther up the beach. Long period swell always increases the
chance for sneaker waves, but that's particularly true this
weekend 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 Monday evening for CAZ006-505-
509-529-530.
PZ...Small Craft Advisory from 9 AM to 9 PM PDT Sunday for Mry Bay.
Small Craft Advisory from 9 AM Sunday to 3 AM PDT Monday for
Pigeon Pt to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras
Blancas 0-10 nm.
&&
$$
SHORT TERM...Sarment
LONG TERM....Sarment
AVIATION...DialH
MARINE...DialH
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Prepared by Boulder-Creek.com Weather at: Sat Sep 5 22:30:03 PDT 2026
From the National Weather Service
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