FXUS66 KMTR 110442
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
942 PM PDT Fri Jul 10 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 127 PM PDT Fri Jul 10 2026
- Warmer temperatures continue into next week with Moderate
HeatRisk early next week
- 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 127 PM PDT Fri Jul 10 2026
(This evening through Saturday night)
Strengthening high pressure over southern California is shifting
eastward toward the Desert Southwest. This has result in a gradual
warming and drying trend across the interior and higher
elevations that will persist through early next week. Meanwhile, a
persistent marine layer around 1,000 feet will gradually compress
to around 500 feet over the weekend and maintain cooler
conditions near the coast. Thus, afternoon maximum forecast
temperatures today will be in the upper 50s to 60s near the coast,
60s/70s around the bays and locations adjacent to the bays, and
80s to middle 90s inland. Meanwhile, the warmest interior
locations of the Monterey County have a greater than 70%
probability of reaching 100 degrees F.
Again for tonight, may see some mist/light drizzle at the coast
as low clouds push locally inland into the coastal adjacent
valleys. Otherwise, temperatures look to cool into the 50s
overnight into Saturday morning for most lower elevations.
However, the higher elevations (especially across the Central
Coast) will only cool into the 60s to lower 70s as the
aforementioned high pressure continues to build.
For Saturday, temperatures continue to warm by a few degrees with
mostly Minor HeatRisk with pockets of moderate in the warmest
interior valleys.
&&
.LONG TERM...
Issued at 127 PM PDT Fri Jul 10 2026
(Sunday through next Thursday)
Saturday night and into Sunday is when we forecast monsoonal
moisture to advect around the western periphery of the high pressure
over the Desert Southwest. This area of high pressure will continue
to strengthen as it shifts northeastward into the Intermountain West
Sunday and into Monday with Precipitable Water values reaching
between 1.00-1.25" across much of the region. There remains a
great deal of uncertainty in the model guidance with respect to
the amount of MUCAPE (lifting mechanism) to support high-based
thunderstorms. The mid/upper level moisture will be in place and
we have fairly high confidence in this. Thus, expect widespread
mid-to-high level clouds to stream across the region with virga
(precipitation not reaching the surface). As the moisture profile
deepens Monday into Tuesday we expect a slight chance of high-
based rain showers across the Bay Area and Central Coast. All that
being said, this is considered a low probability, high impact
scenario if thunderstorms are able to develop, the fire weather
threat is high. We will continue to monitor the potential for
high-based convection closely!
With respect to temperatures, warm and dry conditions are likely to
persist through much of next week when we see more widespread
Moderate HeatRisk across the region Monday though Wednesday. The
exception will be coastal locations as the marine layer is forecast
to remain around 500 feet in depth. Maximum afternoon temperature
warm slightly (especially inland) through early next week and so do
the overnight lows, this explains the more widespread Moderate
HeatRisk. The amount of mid-to-high level clouds may limit how warm
the afternoons get but also would limit radiative cooling as well.
Beyond Wednesday, the 500 MB Heights and Anomalies indicate high
pressure will remain parked over the Four Corners region and/or
Intermountain West. This will keep temperatures slightly above
seasonal averages with near normal precipitation.
&&
.AVIATION...
(06Z TAFS)
Issued at 935 PM PDT Fri Jul 10 2026
The marine layer stratus bank is regaining organization over the
ocean, while inland locations within the marine layer see clouds
develop overhead. This combination of cloud formation and
advection makes the exact timing of arrival very tricky. The
forecast still leans on persistence, but the confidence is onset
timing is pretty low. I feel better about the clearing times in
the morning, however.
Vicinity of SFO...VFR as of this writing, but the walls are
closing in. OAK is reporting ceilings of 1,000 feet, with HAF at
700. When SFO does get their ceiling, the height should be in
that ballpark.
SFO Bridge Approach...Will fill in later than SFO and clear
earlier.
Monterey Bay Terminals...I have no idea what will happen in the
next few hours. The Monterey Bay is clear, but there is a small
patch of clouds over the Monterey Peninsula that is occasionally
drifting over Jack's Peak to the terminal and retreating back.
Eventually IFR conditions will settle in for the night, but I just
can't say when with any confidence tonight.
&&
.MARINE...
(Tonight through next Thursday)
Issued at 935 PM PDT Fri Jul 10 2026
A fresh NW breeze will diminish to moderate this weekend, as seas
gradually diminish. These more favorable conditions will continue
into early next week before strong winds return late week.
&&
.FIRE WEATHER...
Issued at 127 PM PDT Fri Jul 10 2026
Warm and dry conditions persist through much of next week,
especially away from the coastal marine influences which are
forecast to persist through much of next week. This will increase
fire weather concerns as fuels rapidly dry out. Fire weather
concerns further increase late this weekend into early next week
as a surge of monsoonal moisture advects northward around the
western periphery of the high pressure over the Desert Southwest
and Intermountain West. If thunderstorms are able to develop, dry
lightning and gusty, erratic outflow winds would be the main
hazards. The limiting factor is the lack of instability over our
region those days. Thus, we will continue to closely monitor these
conditions through the weekend. Given the combination of the
potential for dry lightning and rapidly drying fuels, it is
important to stay up to date on the forecast as it evolves.
&&
.BEACHES...
Issued at 450 AM PDT Thu Jul 10 2026
A Beach Hazards Statement remains in effect for Pacific coast
beaches through this 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 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 and in January we reached 2.5 feet
above normal.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 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 9 PM PDT Sunday for Pt Arena to Pt
Reyes 0-10 nm.
Small Craft Advisory until 3 AM PDT Saturday for Pigeon Pt to Pt
Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 3 PM PDT Monday for Pt Arena to Pt
Reyes 10-60 NM.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Flynn
MARINE...Flynn
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Prepared by Boulder-Creek.com Weather at: Fri Jul 10 22:30:02 PDT 2026
From the National Weather Service
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