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000
FXUS66 KMTR 181145
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
445 AM PDT Thu Apr 18 2024

...New MARINE...

.SYNOPSIS...
Issued at 1206 PM PDT Wed Apr 17 2024

Warm temps persist into the weekend with a slight cool off Friday
as a weak trough pushes through. Increased cloudiness late week
with a chance of coastal drizzle. Otherwise seasonal going into
next week.

&&

.SHORT TERM...
(Today and tonight)
Issued at 1228 AM PDT Thu Apr 18 2024

The upper ridge now across the region will begin flattening today in
response to a weak disturbance upstream. The only real change in our
weather pattern as compared to yesterday will be slightly more
robust onshore flow. Therefore coastal areas should be a few degrees
cooler, while warm temperatures prevail inland. Look for highs
ranging from the lower to mid 60s along the coast tho the upper 70s
to around 80 in the warmer inland valleys. While most areas should
see plentiful sunshine outside of some higher clouds there is some
suggestion that low clouds and fog may develop around the Monterey
Bay this morning with the possible development of an Otter Eddy.
Regardless, any lower clouds, should they develop, will mix out by
mid to late morning.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 1228 AM PDT Thu Apr 18 2024

A trough will progress through the region on Friday into early
Saturday. This will bring increased cloud cover and breezy onshore
flow which will result in cooler temperatures. Some patchy
drizzle may also develop during the late night and morning hours
for orographically favorable areas along the coast.

The ridge rebuilds a bit over the weekend with a slight warming
trend. However onshore winds will keep things cooler by the coast.

By Wednesday the ridge will weaken as upstream troughing encroaches
on the area. This trough has a bit more moisture to work with, and
some ensemble members suggests that precipitation may return to part
of the area by mid to late week. However confidence at this point is
low so we`ll await future updates to gain greater clarity in the
details.

&&

.AVIATION...
(12Z TAFS)
Issued at 426 AM PDT Thu Apr 18 2024

While  most areas stay VFR, pockets of fog and lower CIGs will build
in the North Bay and Monterey Bay in the early morning. Expect
light winds through the late morning followed by moderate to
breezy winds in the afternoon as widespread VFR returns. VFR
lasts into Thursday night before stratus moves over the Monterey
Bay and northern portions of the SF Bay.


Vicinity of SFO...VFR through the TAF period. Winds stay light into
the afternoon before moderate westerly winds return. These winds
linger into the night before becoming light and variable.

SFO Bridge Approach...Similar to SFO

Monterey Bay Terminals...Times of patchy fog and lower CIGs
linger into the mid morning, followed by VFR. Expect light winds
into the late morning before moderate westerly winds build for the
afternoon. Winds weaken into the evening as stratus moves inland.
Expect IFR CIGs and some fog into the late night.

&&

.MARINE...
(Today through Tuesday)
Issued at 426 AM PDT Thu Apr 18 2024

Expect light to moderate winds into the weekend before breezy to
gusty northerly winds arrive Saturday afternoon. Another moderate
period northwest swell arrives over the weekend as well as another
light, longer period (18 seconds) southerly swell.

&&

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

$$

SHORT TERM...SPM
LONG TERM....SPM
AVIATION...Murdock
MARINE...Murdock

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