Technical NOAA Weather Discussion

FXUS66 KMTR 270552
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1052 PM PDT Fri Jul 26 2024

...New AVIATION...

.SYNOPSIS...
Issued at 305 AM PDT Fri Jul 26 2024

Temperatures cool down more significantly beginning today with
below average temperatures to persist through mid next week. Some
potential for light drizzle along the coast Friday into Saturday
and Saturday into Sunday.

&&

.UPDATE...
Issued at 844 PM PDT Fri Jul 26 2024

Satellite imagery shows stratus building into the North Bay
valleys, the northern San Francisco Bay, the Monterey Bay region,
and into the Salinas Valley. Expect further stratus development
through the night with the Fort Ord profiler now showing a marine
layer over 2000 feet deep. Stratus will pare back to the coastal
regions during the morning, but could persist all day in the
western half of marin County, the northern San Francisco Bay
(including the city of San Francisco and Oakland), and the
southern Monterey Bay. The forecast remains on track with no
updates necessary.

DialH

&&

.SHORT TERM...
(This evening through tonight) 
Issued at 1254 PM PDT Fri Jul 26 2024

Temperatures look to peak in the mid-to-upper 90's across the far 
interior, 70's and 80's around the South Bay and North Bay valleys, 
and upper 50's to 60's near the coast this afternoon. Tonight, 
expecting more widespread low clouds, fog, and coastal drizzle to 
impact the region as the marine layer deepens. This is in response 
to a mid/upper level trough moving across the region. Minimum 
temperatures are forecast to be in the upper 40's across the colder 
interior spots with 50's elsewhere. 

&&

.LONG TERM...
(Saturday through Thursday)
Issued at 305 AM PDT Fri Jul 26 2024

Temperatures continue to cool Saturday and Sunday with widespread 
70s to 80s expected inland and 60s to 70s expected closer to the 
coast. Upper level troughing will continue to deepen over the 
weekend which will help to keep temperatures cooler and contribute 
to some slight potential for light drizzle. Overnight Friday into 
Saturday and Saturday into Sunday, decent low level moisture at 
850mb and 700mb will support the development of light drizzle to 
light rain along the coast and in areas where upslope ascent is 
favored. Both the NBM and the HRRR pick up on light coastal drizzle 
overnight this weekend with some potential for light showers over 
the marine environment. The NBM is showing very light precipitation 
totals along the coast and bay shoreline with totals ranging from a 
trace to a few hundredths of an inch.

The upper level pattern will become more zonal by early next week 
which will allow for temperatures to warm slightly. In general, 
temperatures are expected to gradually increase a few degrees each 
day beginning Monday but high temperatures will still remain below 
average through mid-week. By mid to late next week, a little more 
uncertainty enters the forecast in regards to how fast high 
temperatures will warm up again. Ensemble guidance indicates ridging 
will start to build over the Western US by mid to late next week but 
cluster analysis indicates that it is less certain where exactly the 
ridge will set up. Temperatures could be slightly warmer depending 
on if the ridge is centered more directly over the West Coast vs 
temperatures could be slightly cooler if the ridge is centered to 
the east of the coast. Regardless, it is looking likely that above 
average temperatures will return with the current forecast and the 
CPC 8-14 day outlook both in support of slightly above average 
temperatures returning by the first week of August.

&&

.AVIATION...
(06Z TAFS)
Issued at 1048 PM PDT Fri Jul 26 2024

MVFR/IFR CIGs continue to move inland overnight, affecting the 
all TAF sites. Winds are expected to stay light to moderate 
overnight, with some pockets of mist and fog forming in areas with
the lightest winds and along the coast. CIGs erode in the inland 
areas by mid morning, while the Monterey Bay sees clearing in the
afternoon, however cloud cover looks to remain over the SF Bay 
for the remainder of the TAF period.

Vicinity of SFO...Expect MVFR/IFR CIGs and moderate winds through
the night and into Saturday morning. CIGs lift to MVFR into 
Saturday afternoon as breezy westerly winds arrive. CIGs are 
expected through the rest of the TAF period.

SFO Bridge Approach...Similar to SFO, with some chances of spotty 
IFR-level cloud cover early Tuesday morning.

Monterey Bay Terminals...LIFR/IFR CIGs and mist push inland this 
evening and last until the late morning before lifting, and eroding 
into the afternoon as breezy winds arrive. CIGs move inland again in 
the late afternoon on Saturday, Filling over MRY.

&&

.MARINE...
(Tonight through next Thursday)
Issued at 844 PM PDT Fri Jul 26 2024

Moderate to breezy Northwest winds linger through the weekend
before easing into the next work week. Expect some hazardous gusts
in the northern outer waters as well as along the Big Sur Coast.
Significant wave heights will continue to abate through the
weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 AM PDT Saturday for SF Bay N of Bay 
     Bridge.

     Small Craft Advisory from 3 PM to 9 PM PDT Saturday for Pt Pinos 
     to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory until 3 AM PDT Sunday for Pt Arena to Pt 
     Reyes 10-60 NM.

     Small Craft Advisory until 3 AM PDT Saturday for Pigeon Pt to Pt 
     Pinos 10-60 NM.

&&

$$

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

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Prepared by Boulder-Creek.com Weather at: Sat Jul 27 00:30:03 PDT 2024
From the National Weather Service