FXUS66 KMTR 181138
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
438 AM PDT Sat Jul 18 2026

...New AVIATION, MARINE...

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

 - Steady or slightly warmer temperatures and more humid through 
   early next week

 - The marine layer prevails through the weekend

&&

.SHORT TERM...
Issued at 1220 AM PDT Sat Jul 18 2026
(Today and tonight)

Onshore winds continue with coastal stratus and patchy mist/fog 
moving inland this morning. Strong high pressure remains located 
over the interior west and an upper level trough remains located 
over the eastern Pacific. High clouds may arrive here today from 
monsoonal moisture located over the Southwest. Daytime highs today
will vary from the mid to upper 60s along the coast to the 70s 
bayside to the 80s and 90s well inland. Tonight lows will cool to 
the 50s except in the 60s in the hills and mountains.

&&

.LONG TERM...
Issued at 1220 AM PDT Sat Jul 18 2026
(Sunday through Friday)

Mid and high clouds will increase early next week as higher 
precipitable water (pw) arrives with the eventual northward 
moving remnants of Elida. Elida is currently a tropical storm ~ 
1100 miles south of Point Conception, but the storm is forecast 
to weaken far before reaching higher latitudes. At this time most
model forecasts are forecasting minimal convective potential early
next week. Daytime highs are forecast to be near to slightly 
above normal next week.

&&

.AVIATION...
(12Z TAFS)
Issued at 436 AM PDT Sat Jul 18 2026

Currently a mixed bag of LIFR-MVFR with the 1,200 foot deep marine 
layer making it to all terminals. Conditions will begin to improve 
by 16Z as stratus retreats to the coast where it'll linger through 
the day. Coastal terminals, namely HAF and MRY, may hold onto an 
MVFR ceiling all day as a result. Persistence forecast on tap with
the biggest change over the last 24 hours being that onshore 
winds have diminished. As a result, ceilings on the cusp of 
IFR/MVFR will likely take longer to reach terminals tonight, 
especially LVK and SJC. Diurnal winds will prevail.

Vicinity of SFO...Currently MVFR with westerly flow. Conditions will 
begin to improve by 16Z with high confidence in VFR by the 
afternoon. High confidence on the return of the MVFR ceiling 
tonight.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently IFR with westerly flow at both 
terminals. Stratus will clear out late morning (SNS) to early 
afternoon (MRY) and remain close to the coast. High confidence in 
ceilings on the cusp of IFR/MVFR returning to the terminals
tonight.

&&

.MARINE...
(Today through Thursday)
Issued at 436 AM PDT Sat Jul 18 2026

Moderate to fresh northwesterly breezes will prevail over the
weekend, diminishing to become moderate by next week. Moderate
seas will prevail. Southerly swell will increase from distant
Tropical Storm Elida as it moves north-northwestward into early
next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&

$$

SHORT TERM...Canepa
LONG TERM....Canepa
AVIATION...Sarment
MARINE...Sarment

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Prepared by Boulder-Creek.com Weather at: Sat Jul 18 06:30:03 PDT 2026