FXUS66 KMTR 020855
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1255 AM PST Mon Mar 2 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 341 AM PST Sun Mar 1 2026
- A series of troughs will bring cooler weather and cloudier
skies through Wednesday
- Strong winds expected along the coast and higher terrain
Wednesday through Friday
- Offshore winds will bring warmer and drier weather into the
weekend
&&
.SHORT TERM...
Issued at 1252 AM PST Mon Mar 2 2026
(Today and tonight)
A cut-off surface low is situated just off the coast of Cape
Mendocino. The associated upper level low and trough has overran
the surface feature and moved inland over northern California.
This forward stacking alignment signals weakening of the surface
feature as the upper level convergence typically found upstream of
the trough is now directly over the surface low. The WPC surface
progs support this development, with the surface low weakening
from 1016 mb as of 06Z to 1020 mb by 18Z. This evolution is an
major hindrance to convection, and I've removed mention of
thunderstorms from the forecast for today. That being said, the
disturbance will still push trough over the next 12 hours,
bringing some isolated areas of light rain and more widespread
drizzle through the morning.
&&
.LONG TERM...
Issued at 1252 AM PST Mon Mar 2 2026
(Tuesday through Sunday)
The long wave pattern is active this week. Following the trough
today, a small ridge will build through Tuesday night before
another, more neutrally tilted trough, moves through Wednesday. The
precipitable water is probably too low to bring any appreciable
rain, but this fast moving trough will bring a cold front followed
by strong winds. Gale force gusts are possible along the coast
and in higher terrain from Wednesday through Friday.
In addition to strong winds behind the front, the skies will quickly
clear as much drier air moves in. The PW will likely drop from
around 0.6" Wednesday morning to 0.3" Wednesday evening (roughly
75th percentile to 10th percentile for this time of year). This dry
air mass is initially coming in from the NW behind the front. As the
upper level flow evolves, an inside slider pattern is likely by
Friday or Saturday. This will bring persistent northerly, offshore
flow through the weekend. The combination of this dry air mass and
adiabatic drying from the offshore winds will keep the relative
humidity noticeably low, with mostly clear skies. Temperatures
will also respond to this pattern, reaching the low to mid 70s
next weekend.
Ensemble clusters more or less agree that the dry inside slider
pattern will stay around in some fashion through the 9th or 10th, so
we don't expect much if any rain in the long term forecast as we
head towards the middle of the month.
&&
.AVIATION...
(06Z TAFS)
Issued at 948 PM PST Sun Mar 1 2026
The new picture from space shows low clouds infiltrating
the region, with TAF sites slowly succumbing to MVFR cigs. Radar
scanned a few areas of extremely light reflectivity over the water
this evening; however, those never really made it to land. Any light
showers or drizzle should develop later tonight, likely closer to
the early morning hours. Opted to push mention of drizzle back and
keep most cigs around MVFR and hinted at IFR cigs due to lower
confidence in that area. Conditions improve mid to late morning,
with clearing skies for the afternoon and evening.
Vicinity of SFO...A batch of stratus has made it to SFO this
evening, perhaps an hour or two earlier than expected. Cigs are
expected to hold at MVFR for at least a few hours, perhaps flirting
with periods of VFR if they don't stay landlocked. Any chances for
drizzle or light rain should happen after 9Z, if the models are
right, and then wrap up mid morning. Clouds will gradually lift or
mix out, leading to VFR conditions by late morning or early
afternoon. There is some signal at lower clouds returning early
Wednesday morning, perhaps between 10-13Z. Confidence was too low to
add at this time.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Well we cleared out for a bit this evening,
but that was short lived as the stratus has returned. Given the
games the stratus has been playing tonight, confidence is a bit
lower in whether or not it will stick around all night. Opted to
keep the more pessimistic forecast of MVFR cigs and hint towards IFR
later should we get any drizzle. Cigs should begin to lift by mid to
late morning, with VFR conditions expected for tomorrow afternoon.
&&
.MARINE...
(Tonight through next Saturday)
Issued at 948 PM PST Sun Mar 1 2026
A few showers will be possible north of the Golden Gate tonight
through early Monday as a weak system moves through. Seas continue
to subside through Wednesday. By Thursday seas build as high
pressure strengthens over the eastern Pacific. The building high
will result in northwest winds to gale force and steepening seas
over 12 feet.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 2 PM this afternoon to 3 AM PST
Tuesday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
&&
$$
SHORT TERM...Flynn
LONG TERM....Flynn
AVIATION...KR
MARINE...KR
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Prepared by Boulder-Creek.com Weather at: Mon Mar 2 02:30:03 PST 2026
From the National Weather Service
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