Technical NOAA Weather Discussion

FXUS66 KMTR 250025
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
525 PM PDT Sat Oct 24 2026

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 914 AM PDT Sat Oct 24 2026

 - Near normal temperatures this weekend, cooling to slightly
   below normal through the remainder of the upcoming week

 - Coastal flooding due to astronomical high tides and thermal 
   expansion this weekend through Thursday

&&

.SHORT TERM...
Issued at 114 PM PDT Sat Oct 24 2026
(This evening through Sunday night)

Clear sky conditions are observed across all of the Bay Area and 
north Central Coast this afternoon. This has allowed temperatures 
to warm to into the upper 60s to lower 70s regionwide. Once the 
sun sets, temperatures will cool into the 50s and bottom out in 
the lower 40s across the North Bay Valleys Sunday morning. 
Elsewhere, expecting upper 40s to low 50s across the remainder of 
the region. There is a greater potential to see fog across the 
Russian River and Petaluma valleys early Sunday morning as the 
lack of offshore flow should allow for decent radiational cooling.
However, incoming high clouds may limit that cooling as a cut-off
mid/upper level low is forecast to push into the Pacific 
Northwest Sunday night into Monday. Expect temperatures to be 
similar on Sunday as they are today, generally within a few 
degrees of normal. 

&&

.LONG TERM...
Issued at 114 PM PDT Sat Oct 24 2026
(Monday through next Friday)

The aforementioned system mainly impacting the Pacific Northwest 
and northern California has the potential to bring very light 
rainfall to the northern coastal waters and far northern portions 
of the North Bay Monday morning, generally only a few hundredths 
of an inch or so. As such, temperatures cool to below normal by a 
few degrees on Monday with a gradual cooling trend throughout the 
remainder of the week as the mid/upper level trough off of the 
West Coast deepens. Cooler, unsettled conditions look to return by
Friday and continue into next weekend. However, confidence has 
lowered since yesterday's writing. Be sure to stay up-to-date with
the latest forecast information from trusted sources. 

&&

.AVIATION...
(00Z TAFS)
Issued at 525 PM PDT Sat Oct 24 2026

24 hour trends are warmer and drier with high confidence VFR 
extends through the evening. Drier air and a clear sky /VFR/ 
tonight to daybreak Sunday will allow radiative cooling which may 
form a few patches of valley fog /IFR-LIFR/ early Sunday. Cool air
drainage winds i.e. land breezes will develop tonight and Sunday 
morning, thermally supported with land temperatures becoming 
cooler than sea surface temperatures (mid 60s, well above October 
normals). Buoy air temps are barely cooler than sea surface temps,
and cooler air is forecast to continue over the coastal waters 
tonight, however it may be difficult for maritime low clouds to 
form depending if combined cooling (mainly from radiative cooling)
can reach dew point temperatures. Cool air drainage breezes may 
help or may ultimately move low clouds away from land and mix the 
low clouds out. 00z TAFs continue to advertise mainly VFR. 

Vicinity of SFO...VFR. West wind 15 knots decreasing to light 
northeasterly late tonight and Sunday morning. West wind 10 knots 
late Sunday afternoon and evening.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR. West to northwest winds 5 to 10
knots decreasing and becoming east to southeast 5 to 10 knots
tonight and Sunday morning. West to northwest winds 10 knots
developing Sunday afternoon. 

&&

.MARINE...
(Tonight through next Thursday)
Issued at 443 PM PDT Sat Oct 24 2026

Gentle to moderate northerly breezes persist into early next week
while becoming northwesterly with occasional fresh gusts. Rough
seas will continue to gradually subside to moderate by Sunday and
remain so through much of next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 3 PM PDT Thursday for CAZ006-506-
     508-529-530.

     Coastal Flood Advisory from 9 AM Monday to 3 PM PDT Thursday for 
     CAZ505-509.

PZ...None.
&&

$$

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

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Prepared by Boulder-Creek.com Weather at: Sat Oct 24 20:30:02 PDT 2026
From the National Weather Service