000
FXUS66 KMTR 280535
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1035 PM PDT Sat May 27 2023

...New AVIATION...

.SYNOPSIS...
Issued at 1209 PM PDT Sat May 27 2023

Overall pattern remains largely unchanged with unseasonably cool
temperatures throughout the forecast period. Typical morning
clouds with inland clearing each afternoon. The long term outlook
suggests this pattern will likely persist into early June.

&&

.SHORT TERM...
(Tonight through Sunday)
Issued at 904 PM PDT Sat May 27 2023

The next low pressure system will arrive from the Pacific Northwest
late tonight and Sunday, increasing onshore winds and cooling causing
patchy light measurable drizzle on the coast and along favorable inland
terrain where orographics are enhanced. Clearing may be slow going
Sunday with continuing onshore winds and with the upper level low over
the cwa. Low clouds returning early Sunday evening and night.

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 1209 PM PDT Sat May 27 2023

The longer term pattern appears to be largely that of persistence
as well with small day-to-day changes. Patchy drizzle can be
expected during the mornings through midweek. There are some hints
at a slight warming trend into the end of the week as the
aforementioned closed low moves out of the area. Overall, the
pattern looks to persist with troughing off the west coast
amplified by a strong ridge of high pressure over central Canada.

&&

.AVIATION...
(06Z TAFS)
Issued at 1033 PM PDT Sat May 27 2023

Slight compression of the marine layer compared to 24-hours ago
results in widespread IFR conditions with only isolated MVFR, but
those are only slightly above 1,000 feet. There is also many
reports of a misty/drizzle combination, so many TAFS have been
updated with -DZ/BR through the overnight period. Only isolated
terminals have a probability for VFR conditions Sunday afternoon.
Went more aggressive keeping clouds at MVFR levels around the
Bay. Regardless, early tomorrow night the cloud deck will come
rolling back in.

Vicinity of SFO...IFR. Patchy mist at times. Winds are west-
southwest 10 to 15 knots. There are occasional gusts over 20
knots, but not consistent so were left out of the TAFs, due to
low confidence in strengthening or persisting. Models are
suggesting that cigs should lift above 1,000 feet, but stronger
confidence in a cloud deck remaining through Sunday, lowering back
to IFR again Sunday night.

SFO Bridge Approach...Clouds are slowly filling in the approach
with bases at or just below 1,000 feet. Slight clearing after 20Z,
though patchy clouds will remain. Clouds will begin to fill in on
approach again after 04Z.

Monterey Bay Terminals...LIFR/IFR conditions. Higher bases inland,
but coastal terminals are already below 500 feet, which will
remain there through the night. Vis reductions are possible due to
mist and drizzle, but with the larger scale weather pattern, this
is not the typical set up for fog, so low confidence on that
impacting area terminals. Some VFR clearing inland, but coastal
terminals will be under the cloud all Sunday, before in moves
inland again Sunday night.

&&

.MARINE...
(Tonight through next Thursday)
Issued at 850 PM PDT Sat May 27 2023

Moderate northwest winds continue through Monday with the
strongest winds over the northern outer waters. Breezy to gusty
westerly winds expected across the San Francisco Bay, San Pablo
Bay, Suisun Bay, and the Delta in the afternoons, then weakening
into the night. Longer period background southerly swell continues
through late next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 AM PDT Sunday for PZZ540-575.

     Small Craft Advisory until 9 PM PDT Sunday for PZZ570.

&&

$$

SHORT TERM...Canepa
LONG TERM....Behringer
AVIATION...DK
MARINE...DialH

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