598
FXUS66 KMTR 150412
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
912 PM PDT Sun Jul 14 2024

...New UPDATE, MARINE...

.SYNOPSIS...
Issued at 200 PM PDT Sun Jul 14 2024

Upper level trough will remain situated along the coast this week,
with temperatures remaining near to slightly below normal through
much of the week, with little day to day fluctuations possible.
Meanwhile, a deep marine layer will linger along the coast this
week, pushing inland each night and receding to the coast during
the day. A minor warming trend may develop late in the work week
and for next weekend.

&&

.UPDATE...
Issued at 912 PM PDT Sun Jul 14 2024

Onshore breezes will usher stratus and fog inland tonight and
Monday morning, clearing back to near the coastline Monday during
the day. Maritime influences continue coastside while inland
valley temperatures have gradually eased back to near mid July
normal temperatures. This is in response to weakening of the high
pressure system aloft, gradually easing temperatures are seen in
the lower to mid troposphere though this evening`s Oakland upper
air sounding still showed the 925 mb level (~ 2,500 feet) and 850
mb level (~ 5,000 feet) temperatures close to the 90th percentile
for mid July. Thus in the temperature inversion i.e. the thermal
belts it`s still warmest in the highest terrain of the Bay Area
and north Central Coast as well as far inland valleys where there
isn`t any maritime influence. The marine layer continues to show
some signs of deepening with lower level temperatures forecast to
continue a net cooling through Tuesday then a gradual warming
redevelops mid to late week.

&&

.SHORT TERM...
(This evening through Monday)
Issued at 200 PM PDT Sun Jul 14 2024

Water vapor imagery continues to show this week disturbance
lifting north and east this afternoon, with the Central Coast now
in the dry sector. As a result, sunny skies are prevailing across
the majority of the region. However, visible imagery shows the marine
layer remains firmly entrenched along the immediate coast. In
fact, Monterey Airport is still trying to clear at this hour, and
while it may briefly, expect the low clouds to roll back in
quickly late this afternoon and evening. Meanwhile, temperatures
this afternoon are running within 2 degrees of where they were at
this time yesterday, with most coastal locations still in the 60s
and inland locations in the mid 70s to lower 80s. Only the hot
spots are in the 90s at this time. Given the marine push expected
this evening, expect it to be very pleasant if you are out and
about. The low clouds and fog will once again push inland this
evening and during the overnight hours. Expect tomorrow to be a
repeat of today, with day temperatures once again within a degree
or two of what we saw today.

&&

.LONG TERM...
(Monday night through next Saturday)
Issued at 200 PM PDT Sun Jul 14 2024

Upper level trough of low pressure will remain along the West
Coast this week, with a series of disturbances moving around the
periphery of this trough. This upper level trough will be the
main driving factor of our weather, keeping near to below normal
conditions prevailing across the region. The little disturbances
though will cause subtle day to day fluctuations. Therefore,
expect a relatively deep marine layer to linger along the coast
for most of the work week, pushing inland each night. As these
disturbances lift along the trough, there will be periods of high
clouds as well. At this time, the instability is even less
impressive than what we were looking at for this current event.
Therefore, think any shower and thunderstorm activity will remain
well to our east, but it does bears watching for Wednesday and
again on Friday. Models are hinting at a bit of a warm up for
Friday and Saturday, but it is short lived. This warm up may also
be in question as the ensembles are trending towards more status
quo, rather than a significant warm up. Will need to watch it as
well. Otherwise, enjoy the week. Palmer

&&

.AVIATION...
(00Z TAFS)
Issued at 459 PM PDT Sun Jul 14 2024

Satellite shows clear skies throughout most of the region with the
exception of Monterey Bay where low ceilings have stuck around.
Therefore, currently a mix of VFR and MVFR. Ceilings are expected
to return creating MVFR/IFR conditions for most of the terminals
tonight and will clear near 16-18Z Monday. Winds are relatively
strong and breezy but will diminish to light to moderate this
evening into the night. Breezy conditions return Monday afternoon.

Vicinity of SFO...VFR currently. Expect MVFR conditions tonight near
08Z, but confidence is moderate, where models show best case and
worse case scenarios of VFR through the TAF period, or ceilings may
lower to IFR between 09-15Z. Onshore strong winds will diminish
overnight to moderate but will rebuild by the afternoon tomorrow.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR currently as stratus has a early
return for KSNS and KMRY stratus lingered into this TAF package.
Expect IFR conditions as we move into the late evening. With some
uncertainty on timing for clearing, expect near 18Z.

&&

.MARINE...
(Tonight through next Saturday)
Issued at 828 PM PDT Sun Jul 14 2024

Any chances of drizzle over the waters have diminished. Gentle to
moderate winds persist today and begin to take on a more
southerly pattern that lasts through the middle part of next week,
but then turns to become more northwesterly beyond then.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&

$$

UPDATE...Canepa
SHORT TERM...Palmer
LONG TERM....Palmer
AVIATION...SO
MARINE...SO

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