Technical NOAA Weather Discussion

FXUS66 KMTR 310451
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
951 PM PDT Sun Aug 30 2026

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 1232 PM PDT Sun Aug 30 2026

 - Slight chance for coastal drizzle during the night and morning
   hours through Tuesday morning

 - Cooling trend continues through at least midweek

&&

.SHORT TERM...
Issued at 1232 PM PDT Sun Aug 30 2026
(This evening through Monday night)

Stratus has retreated to the coast as of early afternoon with 
mostly sunny skies across the interior. Thus, temperatures inland 
temperatures will warm into the 70s to mid 80s and the lower 90s 
across the far interior. Meanwhile, persistent onshore flow and 
the marine layer will maintain cooler conditions near the coast, 
generally reaching into the 60s. 

The marine layer is likely to deepen overnight to around 2000 
feet and with an increased potential for coastal drizzle tonight 
and into midmorning on Monday. Expecting a slower clearing of 
stratus Monday morning as troughing off of the Pacific Northwest 
coast develops and deepens. As such, afternoon maximum 
temperatures will be 5 to 15 degrees below average. Heading into 
Monday night, another round of night/morning drizzle is expected 
along the coast and in the favored upslope regions. 

&&

.LONG TERM...
Issued at 1232 PM PDT Sun Aug 30 2026
(Tuesday through next Saturday)

Tuesday is now forecast to be the coolest day of the week with 
afternoon temperatures some 10 to 20 degrees below normal for this
time of year. Temperatures remain below seasonal averages 
throughout much of next week with the potential for rain 
particularly across the North Bay late week as a weak frontal 
boundary sags southward across the region. This is as a cut-off 
low develops off of the northern California coast Tuesday with 
troughing persisting through the remainder of the week and 
potentially into next weekend. Still keeping an eye on the 
tropical eastern Pacific as it remains fairly active for any 
moisture that may be brought northward into California. 

&&

.AVIATION...
(06Z TAFS)
Issued at 950 PM PDT Sun Aug 30 2026

VFR prevails except for nearly continuous stratus and fog/mist 
/MVFR-IFR/ along the immediate coast from Point Reyes southeastward.
The earlier steady erosion on the northwestern edge of stratus 
has paused while nocturnal radiative cooling is underway; it is 
dry to very dry above the marine layer. Additional coastal stratus,
fog/mist and drizzle will form including an inland intrusion 
tonight and Monday morning. Conditions improve to MVFR-VFR along 
the coastline Monday late morning and afternoon. Robust lower
level cool air advection will deepen the marine layer especially 
Monday through Monday night. Stratus and patchy drizzle redevelop
Monday night and early Tuesday.

Vicinity of SFO...VFR except stratus /MVFR/ ceiling 10z-18z Monday
then a stratus ceiling redevelops 04z Monday evening. West wind 8
to 15 knots.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Stratus /MVFR-IFR/ tonight and Monday 
morning. Tempo light drizzle KMRY 10z-14z, conditions improve to 
MVFR-VFR late Monday morning. Stratus /MVFR/ returns Monday evening.
West to northwest winds 5 to 15 knots.

&&

.MARINE...
(Tonight through next Saturday)
Issued at 934 PM PDT Sun Aug 30 2026

Fresh northwest winds diminish to a moderate breeze overnight,
allowing rough seas to subside to moderate by Monday morning. The
long period southerly swell continues to decrease tonight.
Northwest  to westerly winds remain gentle to moderate through the
remainder of  the work week as slight to moderate NW seas prevail.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt 
     Reyes 0-10 nm.

     Small Craft Advisory until 9 AM PDT Monday for Pt Arena to Pt 
     Reyes 10-60 NM.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Canepa
MARINE...Canepa

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Prepared by Boulder-Creek.com Weather at: Sun Aug 30 22:30:03 PDT 2026
From the National Weather Service