758
FXUS66 KMTR 121144
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
444 AM PDT Sun May 12 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1228 AM PDT Sun May 12 2024

A relatively quiet pattern will develop featuring overnight and
morning coastal clouds with clear skies elsewhere. Inland
temperatures will warm into the 70s and 80s each afternoon with
cool onshore breezes keeping coastal temperatures in the 60s.

&&

.SHORT TERM...
(Today and tonight)
Issued at 1228 AM PDT Sun May 12 2024

The marine layer has deepened appreciably with an inversion height
around 800 to 1200 feet per area profilers. Low stratus is
widespread early this morning with greater inland penetration as
compared to yesterday. For those hoping to view the Aurora your best
bet is to either head inland or into the higher terrain above the
marine inversion. Given the deeper marine layer we`re seeing much
less in the way of fog as compared to yesterday as cloud bases are
generally just a tad above the surface. The large-scale picture
features weak troughing aloft over the West Coast with downstream
ridging over the Desert Southwest region. This pattern will support
the continued deepening of the marine layer with a repeat
performance of low stratus tonight. For today, expect clouds to
gradually clear towards the coast with inland warming. High
temperatures will range from the 60s along the coast, to the 70s for
the marine influenced valleys, to the 80s for the warmest inland
locations. A few hot spots across southern Monterey County may even
eclipse the 90 degree mark. Temperatures tonight will be mostly in
the upper 40s to lower 50s, with readings a bit warmer in the higher
terrain inland.

&&

.LONG TERM...
(Monday through Saturday)
Issued at 1228 AM PDT Sun May 12 2024

Temperatures will cool slightly with onshore flow and weak troughing
aloft persisting. An upper ridge does build/strengthen over the
northeast Pacific by mid week, but it appears our area will remain
along its periphery with no strong signal for a warming trend. In
general high temperatures will range from the 60s along the coast to
the lower-mid 80s for the warmest inland areas. This will only
produce a minor HeatRisk for the warmest locations. Lows will
generally be in the lower to mid 50s. Coastal clouds are likely
during the overnight and AM hours with a gradual clearing towards
the coast each afternoon.

&&

.AVIATION...
(12Z TAFS)
Issued at 426 AM PDT Sun May 12 2024

Currently seeing a mix of VFR-LIFR at the terminals as a marine
layer of about 1,000 feet is being allowed to protrude inland.
Aside from MRY, VFR and breezy onshore flow will prevail by this
afternoon. LIFR-IFR conditions are slated to return to most
terminals tonight with lower confidence at APC and SJC. LVK is the
only terminal that will be VFR through the TAF period.

Vicinity of SFO...Currently VFR with breezy westerly flow,
although IFR stratus is finally beginning to close in on the
terminal. Winds will remain breezy out of the west through the
TAF period. Conditions will improve to VFR by 18Z with IFR
conditions slated to make a return again tonight.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently LIFR with breezy westerly flow
at both terminals. Winds will remain breezy out of the
west/northwest through the TAF period. While there may be brief,
sporadic periods of VFR at MRY this afternoon as the low clouds
retreat towards the Pacific Ocean, the terminal will likely be
impacted by a low ceiling and/or reduced visibility through the
duration of the TAF period. SNS has a better chance of truly
clearing this afternoon with IFR conditions looking to make a
comeback again tonight.

&&

.MARINE...
(Today through Friday)
Issued at 426 AM PDT Sun May 12 2024

Surface high pressure will continue to allow for fair weather and
moderate northwesterly breezes to prevail today. As surface high
pressure over the Eastern Pacific Ocean begins to build and move
east tonight, winds will strengthen from a moderate northwesterly
breeze to a fresh northwesterly breeze. As a result, significant
wave heights will build to 12-15 feet by Tuesday before gradually
abating through the rest of the week.

&&

.BEACHES...
Issued at 719 PM PDT Fri May 10 2024

Long period southwest swell will lead to slightly elevated chances
for sneaker wave and rip current development this weekend.
Conditions are expected to stay below Beach Hazards Statement
criteria as swell height will only be between 1-2 feet. However, in
light of anomalously warm temperatures and increased likelihood of
people traveling to the coast, visitors to the beach should remember
to take safety precautions to prevent being caught by an unexpected
large wave and to never turn your back on the ocean.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM to 9 PM PDT Monday for Mry Bay-Pt
     Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this
     evening for Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt
     Reyes 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Monday
     for Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 9 PM PDT Monday
     for Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...SPM
LONG TERM....SPM
AVIATION...Sarment
MARINE...Sarment

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