FXUS66 KMTR 180035
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
535 PM PDT Fri Jul 17 2026

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 1225 PM PDT Fri Jul 17 2026

 - Cooler and more humid conditions through early next week

 - The marine layer prevails through the weekend

&&

.SHORT TERM...
Issued at 1225 PM PDT Fri Jul 17 2026
(This evening through Saturday night)

A marine layer around 1,200 feet in depth resulted in inland 
intrusion of stratus overnight. That said, current satellite 
trends are show these clouds doing their typical afternoon retreat
to the coast. Afternoon temperatures will be as much as 10 deg F 
below seasonal average, especially in the lower elevations. 

Overnight, expecting stratus to return to the coast this evening 
and penetrate into the inland valleys into early Saturday morning.
This is typical for the month of July. Once low clouds retreat 
back to the coast by mid-to-late morning on Saturday, mostly sunny
skies are forecast for the afternoon highs again slightly below 
average. Rise and repeat for Saturday night. 

&&

.LONG TERM...
Issued at 1225 PM PDT Fri Jul 17 2026
(Sunday through next Thursday)

Still keeping an eye on conditions late this weekend into early 
next week as there is some uncertainty with regards to the 
placement of the ridge to the east and troughing to the west. The 
location of these feature will ultimately drive how much mid-to-
upper level moisture we receive from the tropics and monsoon. We 
will continue to monitor this moisture and Convection-Allowing 
Models (CAMs) over the weekend to see if their are any singles for
convection. Be sure to check back for the latest forecast 
information. 

&&

.AVIATION...
(00Z TAFS)
Issued at 431 PM PDT Fri Jul 17 2026

Stratus is rebuilding along the coastline and is expected to reach
most sites tonight. Moderate confidence that CIGs will be MVFR
with IFR possible along the coast as the marine layer deepens to
around 1000-1200 ft. Guidance indicates LIFR CIGs are possible
right along the coast but confidence is low given the depth of the
marine layer. Winds decrease overnight before moderate onshore
winds return tomorrow afternoon/evening.

Vicinity of SFO...VFR with stratus and MVFR-IFR conditions
returning late this evening. Stratus may filter in as early as 04Z
but will most likely return closer to 06Z. Expect clearing by mid
to late morning with stratus returning tomorrow evening. Diurnally
breezy onshore winds continue.

SFO Bridge Approach...Similar to SFO. 

Monterey Bay Terminals...MVFR-IFR conditions expected tonight with
some potential for fog to develop early Saturday morning.
Confidence is low that fog will develop due to the deeper depth of
the marine layer. Initial guidance indicates clearing at SNS by
18Z with a slightly later clearing (20Z) at MRY. Models again show
the potential for MRY to remain overcast throughout the day so
this may need to be amended.

&&

.MARINE...
(Tonight through next Wednesday)
Issued at 431 PM PDT Fri Jul 17 2026

Moderate northwesterly breezes will continue to ease through this
afternoon and evening. Small craft advisory conditions will
gradually taper off this afternoon and evening across most areas
with exception to the waters north of Point Reyes and along the
immediate coast south of Point Pinos. Moderate to rough seas will
persist through today. Conditions improve Saturday as seas abate
and northwesterly winds diminish.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Pt Arena to 
     Pt Reyes 0-10 nm.

     Small Craft Advisory until 3 AM PDT Saturday for Pt Arena to Pt 
     Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Kennedy
MARINE...CW

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Prepared by Boulder-Creek.com Weather at: Fri Jul 17 18:30:03 PDT 2026