Technical NOAA Weather Discussion

FXUS66 KMTR 162348
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
448 PM PDT Thu Jul 16 2026

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 1226 PM PDT Thu Jul 16 2026

 - Elevated fire weather conditions through this evening

 - Breezy onshore winds through Friday 

 - Gradual cooling and moistening trend through the upcoming 
   weekend

&&

.SHORT TERM...
Issued at 1226 PM PDT Thu Jul 16 2026
(This evening through Friday night)

Lingering stratus around the Monterey Bay has eroded as of this 
writing, however the cooling trend continues today as a result of 
increased onshore winds and the deepening mid/upper level trough 
off of the Pacific Northwest coast. The increased winds will 
result in elevated fire weather conditions this afternoon and 
evening as near critically dry conditions persist across the 
interior and higher terrain of the region. Wind gusts are expected
to reach 25-35 mph in the favored gaps and passes. Please see the
Fire Weather section of the AFD for additional details. 

The marine layer is forecast to deepen to around 1,000 feet 
overnight, resulting in better chances for seeing low clouds 
develop along the coast and into the coastal adjacent valleys. 
That said, there is a low probability of mist and/or drizzle late 
tonight and into Friday morning. Low clouds that do develop will 
retreat back to the coastline by mid-to-late morning. 

By Friday afternoon, the cooling trend will continue with 
temperatures dropping to slightly below seasonal averages. Thus, 
we are expecting upper 50s to 60s near the coast, upper 60s to 
middle 70s just inland, and lower 80s to near 90 deg F (the 
warmest interior spots). Friday night, low clouds are more likely 
to reach into the coastal adjacent valleys and potentially into 
the inland valleys as the marine influences become better 
established. This will also increase the potential for mist and/or
drizzle near the coast. However, probabilities are not high 
enough to include drizzle in the official forecast.

&&

.LONG TERM...
Issued at 1226 PM PDT Thu Jul 16 2026
(Saturday through next Wednesday)

Temperatures will be similar to Friday through much of the 
weekend with slight day-to-day fluctuations depending on the depth
of the marine layer. We continue to monitor tropical and monsoon 
moisture that is forecast to spread across the Bay Area and 
Central Coast late in the weekend into early next week. Tropical 
Storm Elida is forecast by the National Hurricane Center to be a 
hurricane by 5 AM Friday (tomorrow). This system is forecast to 
move out into the open Pacific and not directly impact the region.
However, high pressure placed over the Intermountain West this 
weekend will advect moisture from Elida and monsoon moisture 
northward brining an increased in mid-to-high level clouds on 
Sunday and beyond (this the most likely scenario). The lacking 
ingredient is still instability! Be sure to keep up to date with 
the latest forecast information over the coming days. 

&&

.AVIATION...
(00Z TAFS)
Issued at 448 PM PDT Thu Jul 16 2026

Currently VFR with MVFR-IFR conditions expected overnight. The 
marine layer is expected to deepen to around 1000 ft tonight with 
stratus returning along the coast and SF Bay shoreline. Highest 
confidence in stratus impacting HAF, MRY, and SNS with moderate 
confidence that it will reach STS, APC, OAK, and SFO. Have pushed 
back the arrival of stratus slightly with confidence increasing in a 
late evening/overnight return. Breezy onshore winds continue through 
the evening before winds ease overnight. Expect another round of 
breezy onshore winds during the afternoon/evening hours tomorrow.

Vicinity of SFO...Currently VFR with MVFR CIGs to return overnight. 
Stratus returns early tomorrow morning with moderate confidence that 
it will be on the MVFR-IFR border. There is some potential SFO could 
remain clear all night with the HRRR keeping stratus confined to OAK 
and not filling in across the bay. For now, maintained stratus 
reaching SFO tonight but confidence is low to moderate. Breezy 
onshore winds continue through this evening, weaken overnight, and 
return again during the afternoon/evening tomorrow.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR with stratus to return overnight. 
Moderate confidence that CIGs will be IFR-LIFR tonight with CIGs to 
lower overnight. Some potential for visibility to reduce early 
tomorrow morning but confidence is low to moderate (and necessitates 
LIFR conditions developing). Moderate confidence that CIGs will 
clear by 18-20Z with an early return of stratus likely during the 
evening. Breezy onshore winds return during the afternoon/evening 
again tomorrow.

&&

.MARINE...
(Tonight through next Tuesday)
Issued at 448 PM PDT Thu Jul 16 2026

Moderate to strong northwesterly winds will gradually diminish
late tonight into Friday. Hazardous conditions for small crafts
will persist thought this evening across the coastal waters with
localized gale force gusts expected along the coastal jet regions
of Point Reyes and Point Sur. Moderate to rough seas will prevail
through Friday. Conditions improve Saturday as seas abate and
northwesterly breezes diminish.

&&

.FIRE WEATHER...
Issued at 1226 PM PDT Thu Jul 16 2026

The very warm to hot temperatures we have had this week has 
resulted in fuels rapidly drying. Fire weather concerns will 
remain elevated through this evening with relative humidity 
dropping into the teens and lower twenties across the interior and
higher elevations (away from the marine influences), gusty 
onshore winds, and very dry fuels. This may result in additional 
fire starts particularly across the interior and higher 
elevations. These conditions are gradually forecast to improve as 
the marine layer deepens into Friday and over the weekend. 
Unsettled weather is possible late this weekend and into early 
next week with returning potential for dry thunderstorms and 
gusty, erratic winds. However, the focus remains to the east over 
the Sierra Nevada. 

RGass

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay-SF 
     Bay N of Bay Bridge.

     Small Craft Advisory until 9 AM PDT Friday for Pigeon Pt to Pt 
     Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt 
     Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM-Pt Reyes to 
     Pigeon Pt 0-10 nm.

     Gale Warning until 9 PM PDT this evening for Pt Pinos to Pt 
     Piedras Blancas 0-10 nm.

&&

$$

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

Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook, X, and YouTube at:
www.facebook.com/nwsbayarea
x.com/nwsbayarea
www.youtube.com/nwsbayarea


  
Prepared by Boulder-Creek.com Weather at: Thu Jul 16 20:30:03 PDT 2026
From the National Weather Service