FXUS66 KMTR 281812
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1112 AM PDT Thu Aug 28 2025
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 331 AM PDT Thu Aug 28 2025
- Near normal temperatures today and Friday, slightly warmer for
the weekend
- Quiet weather for the holiday weekend
&&
.SHORT TERM...
Issued at 331 AM PDT Thu Aug 28 2025
(Today and tonight)
Offshore marine layer stratus is once again slow to develop early
this Thursday morning. Persistent onshore flow continues to support
a 2000ft marine layer with a relatively weak vertical temperature
gradient, resulting in reduced stratus coverage than model guidance
progged due to reliance on climatology. The interruption of offshore
northwest surface flow should once again limit stratus redevelopment
late this afternoon and evening. Bumped temperatures up along the
coast from the Bay Area down to Monterey Bay to match closer to what
was realized the past couple of days.
&&
.LONG TERM...
Issued at 331 AM PDT Thu Aug 28 2025
(Friday through Wednesday)
Friday will be similar to today before a subtle pattern change sets
in for the weekend. Expect one more day of interrupted stratus
coverage along the coast with near normal temperatures across the
interior. Low amplitude ridging for the weekend will result in
slightly warmer temperatures, with a return to near normal
temperatures for the beginning of next week. Increasing offshore
northwest surface flow returns Saturday, which will bring cooler
SST's and increasing stratus development along the coast than we've
seen the last few days. However, the marine layer will compress,
limiting its inland penetration somewhat. Otherwise, sunny skies and
light winds for our interior locations through the extended
forecast.
&&
.AVIATION...
(18Z TAFS)
Issued at 1111 AM PDT Thu Aug 28 2025
Nearly a picture perfect from space this morning as satellite shows
mainly clear skies skies. Most sties are now reporting VFR
conditions and this will likely hold through the early evening
hours. The marine layer should remain a bit compressed, perhaps
around 1000ft or less tonight, which should limit the inland
expansion. Most confident that stratus returns to the coastline and
then arrives for some interior valleys around or just after sunrise.
Clearing of the stratus should occur by mid to late morning, with
another afternoon of VFR conditions on Friday.
Vicinity of SFO...VFR conditions should prevail until early Friday
morning, with the main concern for this afternoon being a period of
breezy west-northwest to westerly winds up to 20-25kt. Confidence is
moderate that SFO will will see a period of MVFR cigs Friday
morning, thus opted to go with a semi-persistance based forecast
given the marine layer should be similar.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Moderate confidence in stratus tonight,
with stratus potentially arriving as early as 3Z and then holding
through the overnight hours. Uncertainty is more so on timing and
how low the CIGs go. Guidance hints at the possibility of IFR to
LIFR near or shortly after sunrise. Skies should clear by late
morning.
&&
.MARINE...
(Today through Tuesday)
Issued at 1111 AM PDT Thu Aug 28 2025
Light to moderate winds and seas continue across the coastal
waters through the end of the week. Seas build and fresh to strong
gusts develop over the weekend bringing hazardous conditions
across the coastal waters into the next work week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&
$$
SHORT TERM...JM
LONG TERM....JM
AVIATION...KR
MARINE...KR
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Prepared by Boulder-Creek.com Weather at: Thu Aug 28 14:30:03 PDT 2025
From the National Weather Service
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