FXUS66 KMTR 280523
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1023 PM PDT Mon Apr 27 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1055 AM PDT Mon Apr 27 2026
- Warming and drying trend kicks off Tuesday, peaking Thursday
and Friday
- Cooler conditions return this weekend with a chance of rain
&&
.SHORT TERM...
Issued at 1055 AM PDT Mon Apr 27 2026
(This afternoon through tonight)
Isolated light rain showers are continuing with the help of remnant
surface troughing across the Bay Area. Activity will wane this
afternoon, giving way to a mix of sun and clouds and below normal
temperatures. With remnant moisture, low clouds will return to
bayshore and coastal locations tonight as the lower levels
destabilize.
&&
.LONG TERM...
Issued at 1055 AM PDT Mon Apr 27 2026
(Tuesday through Sunday)
The upper-level troughing that brought us light rain over the
weekend will pinch off a cutoff low as upper-level longwave ridging
moves in from the Eastern Pacific Ocean. This will result in a
warming and drying trend with temperatures rebounding to near to
slightly above normal. The warmest day of the week will be on
Thursday for the Bay Area and Friday for the Central Coast. The
locations of the two features, ridge over the Pacific Northwest and
low off the coast of Southern California, will support light
offshore flow during the overnight hours. Subsidence aloft and
offshore flow in the higher terrain will likely yield a shallow
marine layer that will only impact coastal locations. Global
ensemble clusters are in agreement that the ridge will get tamped
down by an approaching upper-level trough as we approach the
weekend. There is some uncertainty on how we get there, but by
Sunday it is likely that there will be an upper-level low off the
California Coast. While there's no measurable precipitation in the
forecast right now, this will renew chances for rainfall as we head
into next week.
&&
.AVIATION...
(06Z TAFS)
Issued at 1023 PM PDT Mon Apr 27 2026
Generally VFR conditions at present, with MVFR stratus expanding
across the coastal valleys through the night. Stratus will dissipate
Tuesday morning with gentle to moderate onshore pattern winds
developing in the afternoon hours, with stratus beginning to develop
on Tuesday evening, although the highest probabilities of stratus
development at the terminals fall after the end of the 24-hour TAF
period.
Vicinity of SFO... VFR with some low clouds for the next few hours,
with MVFR stratus developing early Tuesday morning before
dissipating later that morning. Moderate west-northwest winds will
develop in the afternoon and evening hours before diminishing in the
late evening. High resolution models depict stratus flowing across
the Golden Gate late Tuesday evening, with low confidence of impacts
to the terminal itself before the end of the TAF period. Greater
confidence in earlier impacts at OAK.
SFO Bridge Approach... Similar to SFO.
Monterey Bay Terminals... MVFR ceilings will develop overnight
before diminishing in the later hours of Tuesday morning. Gentle to
moderate northwest winds Tuesday afternoon and evening, otherwise
light drainage flow persists in the overnight and morning hours.
&&
.MARINE...
(Tonight through next Sunday)
Issued at 1023 PM PDT Mon Apr 27 2026
High pressure off the Pacific Northwest coast and low pressure
inland will maintain northwesterly flow over the coastal waters.
Moderate to fresh breezes will develop Tuesday as high pressure
strengthens. These stronger winds will build rough seas of 8-12
feet across exposed waters later in the week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM Tuesday to 3 PM PDT Wednesday for
Pt Arena to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...Sarment
LONG TERM....Sarment
AVIATION...DialH
MARINE...MM
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
Prepared by Boulder-Creek.com Weather at: Mon Apr 27 22:30:03 PDT 2026
From the National Weather Service
|