-- Discussion containing changed information from previous version are highlighted. --
727
FXUS66 KMTR 211737
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1037 AM PDT Tue May 21 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1224 PM PDT Mon May 20 2024

Typical summer-like pattern to persist throughout the first half of
the week. Temperatures are forecast to dip below seasonal averages
by the upcoming weekend as an upper level trough impacts the
region.

&&

.UPDATE...
Issued at 822 AM PDT Tue May 21 2024

Clear skies over most of the region this morning with the
exception of Monterey Bay and within the Salinas Valley. Satellite
shows low stratus pretty socked in, but most of that will clear
out by late morning. Get ready for some warm temperatures today!
Forecast remains on track on expecting temperatures up to mid 80s
inland. North Bay is already seeing around 3-4 temperatures higher
compared to yesterday morning. If you plan to enjoy the warm
temperatures, be sure to hydrate!

SO

&&

.SHORT TERM...
(Today and tonight)
Issued at 321 AM PDT Tue May 21 2024

Similar to the past few days, stratus is confined to coastal regions
with the highest concentrations in the Monterey Bay, portions of the
Central Coast, and the Salinas Valley with dissipation expected by
mid-morning. The main story for tomorrow continues to be the high
temperatures and minor heat risk expected throughout the Bay Area
and portions of the Central Coast. Temperatures are still expected
to peak Tuesday before a slight cool down begins Wednesday.
Inland high temperatures will be 5 to 8 degrees above average with
increasingly northerly flow bringing drier and warmer conditions.
Temperatures will range from the 70s to 80s inland with peak
temperatures in the mid to upper 80s across the North Bay and
portions of the East Bay. Along the coast, onshore flow continues
which will keep high temperatures seasonal to slightly below average
with highs ranging from the upper 50s to mid 60s.

Minimum RH values will be between 15-35% inland with drier
conditions extending closer to the coastline as offshore flow aloft
continues. Areas directly adjacent to the will see minimum RH values
between 50-75% with onshore flow increasing atmospheric moisture.
Given Tuesday`s warmer and drier conditions, minor heat risk is
expected for almost all of the Bay Area and Central Coast. People
who are extremely sensitive to heat should take precautions while
outdoors and remember to drink plenty of water.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 321 AM PDT Tue May 21 2024

Temperatures cool slightly Wednesday and Thursday before a more
substantial cool down begins Friday into the weekend as upper level
troughing moves into the Bay Area. High temperatures are expected to
be on average 5 to 10 degrees below average next weekend with
widespread highs in the mid 60s to low 70s inland. Coastal highs
will range from the mid 50s to low 60s. Ensemble guidance is
starting to agree that some light precipitation (generally less than
0.1") may occur as upper level troughing moves through next weekend.
The Climate Prediction Center continues the trend of below average
temperatures and slightly above average precipitation through the
end of the month. To put this into context, May traditionally marks
the beginning of the dry season for our region as the Pacific High
shifts southward and deflects surface low pressure systems
northwards of us. Most stations typically observe little to no
precipitation from late May through August so any rainfall at all
can be considered above average. To sum it up, any precipitation
that does occur this weekend is expected be light and non-impactful
but can be considered above average given that we typically see

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 1020 AM PDT Tue May 21 2024

Currently VFR at all terminals with stratus hugging the coastline
from the San Francisco Peninsula down to Point Conception. Moderate-
high confidence of VFR through the TAF period at all terminals with
the exception of the Monterey Bay terminals of MRY and SNS.

Vicinity of SFO...Currently VFR with offshore flow. VFR through the
TAF period. Winds will transition to become breezy out of the west
by this afternoon with gusts up to 25 knots to be expected.
Confidence is moderate that the terminal will evade a ceiling;
however, there will likely be low clouds in the FL010-FL030 range
between 10Z and 16Z. Winds will become breezy out of the west again
tomorrow afternoon with gusts up to 25 knots to be expected.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR with westerly flow at MRY
and VFR with northerly flow at SNS. Moderate-high confidence that
MVFR stratus will return to both terminals overnight, with lower
confidence on if ceilings will dip into IFR territory. Winds will
remain breezy through the TAF period and out of the west/southwest
for MRY and out of the west/northwest for SNS.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
(Today through Sunday)
Issued at 1020 AM PDT Tue May 21 2024

Building surface high pressure over the Eastern Pacific Ocean
will continue to allow for strong northwesterly winds to prevail
through Thursday, with gale force gusts across the outer coastal
waters. Expect hazardous conditions and steeper wind waves during
the week. Winds diminish heading into the weekend as surface high
pressure over the Eastern Pacific Ocean weakens and retrogrades
to the west.
-- End Changed Discussion --

&&

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

     Small Craft Advisory from 3 PM this afternoon to 3 PM PDT
     Wednesday for Pt Reyes to Pigeon Pt 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.

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

     Gale Warning until 3 PM PDT Wednesday for Pt Arena to Pt Reyes
     10-60 NM.

     Gale Warning until 3 AM PDT Wednesday for Pigeon Pt to Pt Pinos
     10-60 NM.

&&

$$

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

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