FXUS66 KMTR 080729
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1229 AM PDT Wed Jul 8 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 1229 AM PDT Wed Jul 8 2026
- A warming trend today through the weekend
- Long period southwest swell causes an increased risk of sneaker
waves and strong rip currents through Friday
- Coastal Flood Advisory for up to 1.7 feet of inundation above
ground level is possible in low-lying areas near shorelines and
tidal waterways
- Potential for thunderstorms and elevated fire weather concerns
late this weekend into early next week
&&
.SHORT TERM...
Issued at 1229 AM PDT Wed Jul 8 2026
(Today and tonight)
A 500 mb high pressure system centered over the southwestern
states is forecast to continue shifting essentially westward to
southern California and northern Mexico over the next 24 hours. A
500 mb trough of low pressure is over the eastern Pacific. Onshore
winds will continue to usher stratus inland through morning, with
diurnal surface warming mixing out much of the stratus by late
morning and afternoon. Daytime highs will be in the 60s coastside,
60s/70s bayside to the 80s/90s inland.
Stratus returns tonight. Lows will be in the 50s except lower to
mid 60s at higher elevations tonight.
&&
.LONG TERM...
Issued at 1229 AM PDT Wed Jul 8 2026
(Thursday through Tuesday)
The aforementioned high pressure system will be nearly stationary
on Thursday then it'll shift northeastward Friday through early
next week. Daytime highs will be coolest along the coast with 60s,
60s/70s bayside and in the 80s/90s inland to the lower 100s far
inland mainly over the southern interior. Night-time lows will
cool to the 50s/60s.
Southerly winds aloft on the periphery of the high will rather
quickly transport mid-level sub-tropical/tropical moisture to our
forecast area beginning Saturday evening and night. There are
hints in the GFS for example that a mid level moisture gradient
to our southwest will straddle the coastal waters and offshore
waters late Saturday/Sunday then again Tuesday. The intrusion of
dry air above lifting moist air parcels/layers tilt the lapse rates
much more steeply leading to convection. There may be a temporary
increase in mid level instability traversing our forecast area
early in the week. A sign for minimal potential, at this time at
least GFS forecast soundings are indicating essentially no
convective potential (mucape) over our forecast area.
&&
.AVIATION...
(06Z TAFS)
Issued at 947 PM PDT Tue Jul 7 2026
The marine layer stratus is making its nightly push inland. Some
drier air has filtered into the North Bay, keeping STS and APC in
the clear for now. Eventually all terminals will develop a
ceiling, with a lowering trend through the night. Expect MVFR-IFR
flight conditions.
Vicinity of SFO...The ceiling is 1,300 feet at the moment, and
slowly lowering. MVFR conditions are likely to persist through
around 09Z when the chance for high IFR increases. Winds will
remain WNW, strengthening to around 20 knots tomorrow afternoon.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals... Despite the dry pocket over the
Monterey Bay, coastal convergence is enough to sustain a ceiling
over both MRY and SNS, and it's now unlikely to improve as the
night wares on. Expect MVFR conditions to gradually lower to high
IFR by sunrise.
&&
.MARINE...
(Tonight through next Monday)
Issued at 947 PM PDT Tue Jul 7 2026
Buoys are reporting a fresh to strong NW breeze across the
coastal waters. These conditions will persist for several days as
rough seas build to 8-12 feet. Meanwhile a low, long period
SW swell will persist through Friday.
&&
.FIRE WEATHER...
Issued at 127 PM PDT Tue Jul 7 2026
Warmer and drier conditions return Thursday and continue into this
weekend. This will increase fire weather concerns slightly as
fuels rapidly dry across the interior. Fire weather concerns
further increase late this weekend into early next week as a surge
of monsoonal moisture from the Gulf of California brings the
potential for high based convection to the region. If
thunderstorms are able to develop, dry lightning and gusty,
erratic outflow winds would be the main hazards. The current
pattern looks conducive for thunderstorms to develop but this may
change as the event gets closer in time. Given the combination of
potential for dry lightning and dry fuels, it is important to stay
up to date on the forecast for the latest information.
&&
.BEACHES...
Issued at 1238 PM PDT Mon Jul 6 2026
A Beach Hazards Statement remains in effect for Pacific coast
beaches from Tuesday morning through Friday afternoon. Long period
southwesterly swell will create an increased risk of sneaker
waves and strong rip currents, as well as breaking waves up to 10
feet. This will be especially true for south and southwest facing
beaches with moderate to steep slopes along the North Bay, San
Francisco Peninsula, and Santa Cruz coasts. Sneaker waves can
sweep across the shoreline without warning, pulling people into
the sea from rocks, jetties and beaches. Dangerous swimming and
surfing conditions and localized beach erosion can be expected.
Stay off of jetties, piers, rocks, and other waterside
infrastructure. Remain out of the water to avoid hazardous surf
and NEVER turn your back on the ocean. Monitor local weather, surf
and tide forecasts at www.weather.gov/mtr.
A Coastal Flood Advisory is in effect for minor high tide
flooding from Thursday July 9th through Thursday July 16th. The
combination of a perigean spring tide (lunar perigee on 7/13 and
new moon on 7/14) enhanced by 3-6 inches of additional water from
thermal expansion and accumulated sea level rise since the tidal
datum was established (1983-2001) will bring high tides up to 1.7
feet above normal. This will lead to minor flooding of parking
lots, parks and roads with isolated closures expected. For
context, in June we reached 2.0 feet above normal.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Friday afternoon for CAZ006-505-
509-529-530.
Coastal Flood Advisory from 4 PM to 4 AM PDT Thursday for CAZ006-
506-508.
Coastal Flood Advisory from 8 PM Saturday to 4 AM PDT Wednesday
for CAZ505-509-529-530.
PZ...Small Craft Advisory until 3 AM PDT Wednesday for SF Bay N of
Bay Bridge.
Small Craft Advisory until 9 PM PDT Wednesday for Mry Bay.
Small Craft Advisory until 9 AM PDT Friday for 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.
Small Craft Advisory until 3 AM PDT Thursday for Pigeon Pt to Pt
Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.
&&
$$
SHORT TERM...Canepa
LONG TERM....Canepa
AVIATION...Flynn
MARINE...Flynn
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Prepared by Boulder-Creek.com Weather at: Wed Jul 8 00:30:03 PDT 2026
From the National Weather Service
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