Corralitos, California Weather Forecast Discussion

809
FXUS66 KMTR 061554
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
854 AM PDT Mon Oct 6 2025
...New UPDATE, MARINE...
.KEY MESSAGES...
Updated at 418 AM PDT Mon Oct 6 2025
- Warmer and drier conditions through midweek, with moderate
   offshore wind expected today and Tuesday in the higher
   elevations
- Unsettled weather returns late this week
&&
.UPDATE...
Issued at 853 AM PDT Mon Oct 6 2025
Clear sky conditions across much of the region this morning with
offshore flow aloft. The exception is around Half Moon Bay and down
along the Big Sur Coast as a very shallow marine layer remains less
than 500 feet in depth. As a result of the offshore winds,
temperatures will warm-up quickly this morning and into the
afternoon. Maximum temperatures this (Monday) afternoon will warm
into the low to mid 70s along the immediate coastline with low to
upper 80s across inland areas. Downtown San Francisco has around a
12% probability of exceeding 85 degrees F with southeast portions of
the city at around 25%. Places such as Novato, San Rafael, San
Mateo, Redwood City, and Gilroy have a 30-50% chance of exceeding 90
degrees F. These temperatures are generally around 5-10 degrees
above seasonal averages across the North Bay and Bay Area. It is
going to be downright warm this afternoon (and again tomorrow).
RGass
&&
.SHORT TERM...
Issued at 418 AM PDT Mon Oct 6 2025
(Today and tonight)
A relatively weak offshore upper level low will slowly retrograde
during the day today while maintaining a fetch of weak offshore
flow that will tame the marine layer from making progress inland.
Low stratus should remain offshore and be patchy (if present at
all) throughout the day from Monterey Bay down the Big Sur
coastline. With offshore flow today we`ll see warmer than normal
temperatures, with coastal communities feeling the biggest
difference without much help from the marine layer. Overnight lows
into Tuesday will be 5-10 degrees above normal with some elevated
locations in the thermal belts 15+ degrees above normal along
with poor RH recovery.
&&
.LONG TERM...
Issued at 418 AM PDT Mon Oct 6 2025
(Tuesday through Sunday)
Offshore flow will continue to influence max temps on Tuesday,
with lesser certainty near the coast given weak mixed/to
occasionally offshore flow late Tuesday morning into Tuesday
evening. By Wednesday a weak offshore surface trough located
somewhere between the Bay Area and the Big Sur coastline will
further complicate low- layer vertical wind profiles, however
temperatures overall across the the region will be cooler as the
upper level disturbance begins to evolve into an open wave, move
onshore and merge with a deepening trough to the north. The
relatively weak/mixed low level flow along the coast should begin
to become more steadily onshore by late Thursday into Friday. Rain
chance increase Friday into the weekend, however there is still a
lack of consensus in the overall synoptic pattern, along with the
presence of a tropical system in the SE Pacific to further
confuse the NWP models.
&&
.AVIATION...
(12Z TAFS)
Issued at 418 AM PDT Mon Oct 6 2025
Good flying conditions today as light offshore winds keep stratus
under control. Currently VFR across the board (exception KHAF,
expected to clear by sunrise). Dry air from light offshore winds
is resulting in clear skies across much of the region and will
remain that way through today. A couple of exceptions will be
Monterey Bay terminals (see below) and KSTS which has a slight
chance of seeing some local FG impacts around sunrise.
Vicinity of SFO...VFR. Biggest aviation impact this period will be
light offshore winds. Today and Tuesday, anticipating light NE
winds during the morning hours until just after noon when onshore
flow kicks in.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR through today. As offshore pressure
gradient weakens, marine stratus returns tonight into Tuesday
morning. Low confidence in coverage since some dry air will still
be lingering, and the marine layer will take some time to reform.
&&
.MARINE...
(Today through Saturday)
Issued at 853 AM PDT Mon Oct 6 2025
Light to moderate winds accompanied by low to moderate seas will
prevail through Tuesday. An approaching system will begin to
increase winds and seas mid to late week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&
$$
SHORT TERM...JM
LONG TERM....JM
AVIATION...Behringer
MARINE...BFG
Visit us at www.weather.gov/sanfrancisco
Follow us on Facebook, X, and YouTube at:
www.facebook.com/nwsbayarea
x.com/nwsbayarea
www.youtube.com/nwsbayarea

NWS MTR Office Area Forecast Discussion