483
FXUS66 KMTR 122348
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
448 PM PDT Mon Aug 12 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1255 AM PDT Mon Aug 12 2024

Cooling trend continues today, with a slight warmup beginning
Tuesday and temperatures at or below seasonal averages through the
rest of the week.

&&

.SHORT TERM...
(This evening through Tuesday)
Issued at 300 PM PDT Mon Aug 12 2024

A progressive upper level trough axis will pass across our area this
afternoon, shifting east into the Central Valley later tonight. As
expected, temperatures are running about 5-10 degrees cooler than
normal across our locations away from the marine boundary layer
influence. Marine layer stratus is mostly clearing out as the upper
trough sweeps across the region. Low stratus clouds will return this
evening with onshore surface flow filling in low lying areas and
valleys along the coast along with periods of drizzle and fog from
the North Bay down to Monterey Bay. Temperatures tomorrow will be
very similar to today, maybe a degree or two warmer in some spots.

&&

.LONG TERM...
(Tuesday night through next Sunday)
Issued at 300 PM PDT Mon Aug 12 2024

Extended forecast remains quiet with temperatures remaining near or
slightly below normal for at least the next seven to ten days. A
brief interruption in the cooler temperatures will be Wednesday, when
a progressive shortwave ridge quickly amplifies as it tracks west
across our area, allowing temperatures to tick a few degrees warmer
for one day. Breezy winds can be expected later this week,
especially at higher elevations as a series of low amplitude
shortwave energy stream across our area out ahead of a deeper trough
that will develop over the Pacific Northwest later this week into
the weekend.

&&

.AVIATION...
(00Z TAFS)
Issued at 443 PM PDT Mon Aug 12 2024

Currently VFR at all terminals with a marine layer depth of about
1,000 feet. Moderate confidence on all terminals except LVK, SFO,
and SJC developing a ceiling tonight. Widespread VFR will prevail
by tomorrow afternoon. Winds will remain onshore through the TAF
period. Slant range visibilities will likely be reduced due to
haze and smoke.

Vicinity of SFO...Currently VFR with westerly flow. Moderate
confidence on the terminal evading a ceiling overnight, but if one
were to develop it would likely be a "sunrise surprise" scenario in
the 12Z-16Z timeframe in the IFR to low-end MVFR range. Winds
will prevail out of the west through the TAF period with gusts up
to 25 knots to be expected in the afternoons and evenings.

SFO Bridge Approach...Low clouds will be present 11Z-16Z.

Monterey Bay Terminals...Currently VFR with northwesterly flow at
both terminals. High confidence in LIFR ceilings impacting both
terminals overnight with VFR prevailing by tomorrow afternoon.
Winds will prevail out of the west/northwest through the TAF
period.

&&

.MARINE...
(Tonight through next Saturday)
Issued at 443 PM PDT Mon Aug 12 2024

Moderate to fresh northwesterly winds continue with coastal jets
developing off of Point Arena and Big Sur by mid week. Strong
gusts  will become more widespread over the outer waters beginning
Tuesday  night into Wednesday. Significant wave heights will peak
between 5  to 8 feet and continue to abate over the majority of
the coastal  waters through mid week. Moderate northwesterly swell
and light  southerly swell continues to move through the waters.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Tuesday for Pt Arena to Pt
     Reyes 0-10 nm.

     Small Craft Advisory from 9 AM Tuesday to 3 AM PDT Wednesday for
     Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory until 3 AM PDT Wednesday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

     Small Craft Advisory from 9 PM this evening to 9 AM PDT Tuesday
     for Pt Arena to Pt Reyes 10-60 NM.

     Small Craft Advisory from 3 PM Tuesday to 3 AM PDT Wednesday for
     Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60
     NM.

&&

$$

SHORT TERM...JM
LONG TERM....JM
AVIATION...Sarment
MARINE...Kennedy

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