154
FXUS66 KMTR 091732
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1032 AM PDT Sun Jun 9 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 306 AM PDT Sun Jun 9 2024

Inland high temperatures reach into the 80s today with 70s closer
to the SF Bay with high clouds present as a weak trough moves
through our region. Beginning tomorrow, high pressure resumes,
leading into our next warmup. The warmest day will be Tuesday,
with Moderate HeatRisk expected for inland regions, and Minor
everywhere else. High temperatures dip just a few degrees
Wednesday, but will cool most significantly Thursday as troughing
resumes.

&&

.SHORT TERM...
(Today and tonight)
Issued at 306 AM PDT Sun Jun 9 2024

At this moment, its a quiet night, with satellite
showing passing high clouds moving through the region as a weak
trough moves through. Very Little stratus is to be found along
the coast, having been mixed out. Temperatures along the coast and
bay where stratus was present yesterday are generally 1-2 degrees
cooler now than they were the same time last night, likely due to
greater radiative cooling ability now that the "blanket" of
stratus has been eroded. Looking forwards to the the day today,
high temperatures will be in the mid to low 80s for inland areas,
with low to mid 70s expected closer to the SF Bay. Along the
coastline, high temps will be in the upper 50s to low 60s.
Temperatures will generally be just a few degrees lower than
normal for bay and coastal areas today, with inland areas seeing
temperatures perhaps just 1 or 2 degrees below normal. The one
exception appears to be the far northern portions of Sonoma and
Napa counties where the warmest temperatures will be found; here
temperatures will be about 3-5 degrees above normal.

The aforementioned upper level trough will also help create breezier
conditions in the afternoon once more today, largely in the Salinas
valley and the East Bay counties bordering the delta region. Wind
gusts towards the 25-30 mph mark in these favored areas are
possible, but then ease into the nighttime.

In short, its a lovely June weekend. Get out and enjoy it before our
next heat wave begins Monday!

&&

.LONG TERM...
(Monday through Saturday)
Issued at 306 AM PDT Sun Jun 9 2024

Starting Monday, our visiting upper level trough begins to be cut
off, eventually forming a cut-off low. Without any good steering
mechanism, models show this low lingering off the southern CA
through at least the midweek. However, the larger focus will be the
ridging that develops in its place over our region tomorrow that
will bring us our next warm up.

Starting Monday, high temperatures are expected to reach into the
high 80s and lower 90s for inland regions, with the warmest spots
achieving temperatures in the mid 90s. Tuesday, the warmest
temperatures are expected with temperature increasing a few degrees
more. Mid to upper 90s are expected for inland areas, as well as
low 100s in the northern portions of Sonoma and Napa counties, the
southern Salinas valley and San Benito county, and more generally
along the easternmost portions of counties bordering the Central
Valley. Warm temperatures persist into Wednesday, but begin to
drop by a few degrees, with high temps largely similar to those on
Monday. Coastal areas throughout this event will remain
relatively cool in the mid to upper 60s, perhaps touching the
lower 70s on Tuesday as onshore flow helps maintain more
comfortable temperatures. As it currently stands, models continue
to show light onshore flow persisting.

With these warmer temperatures comes increased HeatRisk. While
Monday and Wednesday see largely Minor HeatRisk for the majority of
our area, Tuesday will have many inland locations achieving Moderate
levels of HeatRisk while coastal areas remain in the Minor category.
This moderate category indicates a level of heat that affects most
individuals sensitive to heat, such as those that are ill, elderly,
very young, or without shelter or a means to cool themselves such as
air conditioning. As we draw nearer to this event, keep in mind that
even if only Minor HeatRisk is indicated, that heat related illness
and impacts can affect anyone, especially when heat is prolonged.
Its never a bad idea to make sure you are staying adequately
hydrated during times of warmer temperatures, taking breaks in the
shade if working outdoors, and to check in on loved ones who perhaps
fall into the demographics of those sensitive to heat. Additionally,
if planning to visit the coast or a body of water to cool off, make
sure you wear a lifejacket, swim ideally near a lifeguard, and be
aware of the risks of cold water shock.

Towards Thursday, high temperatures decrease and begin to cool off
as troughing resumes and the cutoff low rejoins upper level flow and
lifts out to our east.

&&

.AVIATION...
(18Z TAFS)
Issued at 1022 AM PDT Sun Jun 9 2024

Lingering low and mid level clouds as a weak upper level trough
exits the area. VFR through the day today with breezy onshore flow
for coastal and gap areas. Moderate confidence in return of
MVFR/IFR stratus overnight by about sunset for Bay Area terminals,
slightly later for North Bay. All terminals clearing to VFR by mid
morning Monday.

Vicinity of SFO...VFR through this afternoon with some occasional
lingering low clouds. Breezy onshore W/NW flow with gusts around
25 kts this afternoon, diminishing into the evening. Moderate
confidence in MVFR/IFR stratus around sunset (high confidence in
cigs, lower confidence in timing).

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR through the afternoon with light
onshore flow. High confidence in MVFR/IFR cigs overnight tonight
and clearing to VFR once again by late Monday morning.

&&

.MARINE...
(Today through Friday)
Issued at 1022 AM PDT Sun Jun 9 2024

The gradient between subtropical high pressure in the East
Pacific, and lower pressure over the western US is supporting a
fresh to strong NW breeze and rough seas across the coastal
waters. The overall pattern will remain fairly stable over the
next week although the high pressure will meander closer to the
coast at times, bringing periods of near gale force winds and
very rough seas. The first push is expected mid-week, with another
over the upcoming weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this
     evening for Mry Bay.

     Small Craft Advisory until 3 AM PDT Tuesday for Pigeon Pt to Pt
     Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory until 9 AM PDT Monday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

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

     Small Craft Advisory until 9 AM PDT Tuesday for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

SHORT TERM...AC
LONG TERM....AC
AVIATION...Behringer
MARINE...Flynn

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