FXUS66 KMTR 080500
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1000 PM PDT Tue Jul 7 2026
...New AVIATION, MARINE, BEACHES...
.KEY MESSAGES...
Updated at 1253 PM PDT Tue Jul 7 2026
- Seasonably cool temperatures today before a warming trend
begins Wednesday through the weekend
- Long period southwest swell causes an increased risk of sneaker
waves and strong rip currents today through Friday
- Potential for thunderstorms and elevated fire weather concerns
late this weekend into early next week
&&
.SHORT TERM...
Issued at 1253 PM PDT Tue Jul 7 2026
(This evening through Wednesday night)
Seasonal to seasonally cool temperatures continue today into
tomorrow thanks to a deep marine layer and expansive layer of marine
stratus. The marine layer is forecast to remain between 1500-2000
feet through tomorrow as troughing continues to our west over the
Pacific Ocean. Marine stratus will return across much of the
interior Bay Area and Central Coast tonight with pockets of fog
possible across the North Bay Valleys and along the coast. If you
are missing clear skies today, you will have a better chance at
seeing them tomorrow. Confidence is higher tomorrow that stratus
will recede by late morning/early afternoon across the interior as
surface high pressure strengthens and the marine layer compresses to
around 1000-1500 feet. The marine layer will help keep much of the
area seasonally cool with high temperatures in the 50s to 60s along
the coast and 70s to 80s across the interior Bay Area. The one
exception will be the interior Central Coast where temperatures are
seasonal to seasonally warm in the 80s to 90s. Marine layer
influence on the interior Central Coast is minimal with building
high pressure across the desert southwest having a stronger
influence on that region. Breezy afternoon and evening winds
continue across mountain gaps/passes (the Salinas Valley, San Bruno
Gap, the Altamont Pass) and along the coast.
&&
.LONG TERM...
Issued at 1253 PM PDT Tue Jul 7 2026
(Thursday through next Monday)
The forecast begins to change Wednesday night into Thursday as high
pressure across the Desert Southwest retrogrades, becoming centered
more over Southern California. This allows temperatures to warm up
by a few (~4-5) degrees outside of coastal areas and the bay
shoreline. For the interior Bay Area this results in temperatures in
the mid to upper 80s with pockets of 90s in the far North Bay and
far interior East Bay. The warmest locations will be in the interior
Central Coast where temperatures look to be in the low 100s Thursday
and Friday. The NBM deterministic is running closer to the 90th
percentile for the interior Central Coast but even the mean NBM
forecast keeps temperatures around 100. All that to say,
whatever way you look at it the interior Central Coast will be hot
on Thursday. Temperatures will remain fairly similar to this through
the rest of the extended forecast as upper level ridging builds over
California. High temperatures will fluctuate by 1-2 degrees but will
largely stay in the 80s to low 90s across the interior, 60s along
the coast, 70s along the bay shoreline, and 90s to low 100s across
the interior Central Coast. Long range models are showing early
potential for strong upper level ridging to build across the
Intermountain West early to mid next week. This is likely to bring
above normal temperatures with initial guidance for Tuesday showing
temperatures warming across the interior East Bay and interior
Central Coast. This is certainly something to keep an eye on if not
for the heat impacts but the fire weather risk.
In addition to the hotter conditions expected in the long term,
there is the potential for dry lightning Sunday into Monday. On the
synoptic scale, upper level high pressure will more northeastward
(towards the Intermountain West) Sunday into Monday while upper
level troughing deepens over the Pacific Ocean. Our region is still
primarily influenced by the upper level ridge, but, the deepening
trough will result in stronger southeasterly flow across Southern
California, Arizona, and the Gulf of California. This will bring a
surge of monsoonal moisture from the Gulf of California northward
into California. PWAT values look to be between 1-1.5" Sunday into
Monday which is approximately 150-200% of normal for this time of
year. The highest PWAT values are currently forecast across the
Central Coast, South Bay, and East Bay. At the same time, the 700-
500 mb lapse rates are between 7-8 C/km which are favorable for
convection to develop. If all these ingredients are able to come
together, then it is likely we would see high-based thunderstorms
across portions of our CWA. Given the elevated nature of any
potential thunderstorms, any precipitation that falls would
evaporate before reaching the surface. The two most likely hazards
would then be dry lightning and gusty, erratic outflow winds. Hot
and dry conditions this week will prime the environment for fire
starts by further drying out fuels and making them more susceptible
to fire starts if thunderstorms develop. Fire weather concerns are
elevated Sunday into early next week as a result of the dry
lightning threat. While the pattern appears conducive for
thunderstorm development, there remains some uncertainty regarding
specific details. The nature of these specific details may modulate
the risk for a high-based convective event.
This is a good time to stay tuned to the forecast as we move into
the domain of higher resolution short term models and the forecast
becomes clearer later this week.
&&
.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...Kennedy
LONG TERM....Kennedy
AVIATION...Flynn
MARINE...Flynn
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Prepared by Boulder-Creek.com Weather at: Tue Jul 7 22:30:04 PDT 2026
From the National Weather Service
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