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000
FXUS66 KMTR 240618
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1118 PM PDT Tue Apr 23 2024

...New AVIATION...

.SYNOPSIS...
Issued at 113 PM PDT Tue Apr 23 2024

Cool, cloudy conditions continue into the late week with coastal
drizzle possible. Modestly warmer weather and less persistent
cloud cover is expected over the weekend and into next week.

 &&

.UPDATE...
Issued at 902 PM PDT Tue Apr 23 2024

Similar to last night, coastal stratus is moving inland with
overcast conditions expected overnight through tomorrow morning.
Coastal drizzle is possible again tonight with light accumulation
totals (less than a tenth of an inch) expected along the coastal
ranges.

Comparing yesterday and today, today`s high temperatures were
much cooler than yesterday`s with highs dropping on average 10-15
degrees. A few stations had even greater temperature differences
between 15-18 degrees. Take Concord, for example, which had a high
of 83 degrees yesterday but only had a high of 65 today. The
cooler, unsettled weather pattern as described in the forecast
remains on track with below average temperatures to continue
through the end of the work week.

&&

.UPDATE...
Issued at 902 PM PDT Tue Apr 23 2024

Similar to last night, coastal stratus is moving inland with
overcast conditions expected overnight through tomorrow morning.
Coastal drizzle is possible again tonight with light accumulation
totals (less than a tenth of an inch) expected along the coastal
ranges.

Comparing yesterday and today, today`s high temperatures were
much cooler than yesterday`s with highs dropping on average 10-15
degrees. A few stations had even greater temperature differences
between 15-18 degrees. Take Concord, for example, which had a high
of 83 degrees yesterday but only had a high of 65 today. The
cooler, unsettled weather pattern as described in the forecast
remains on track with below average temperatures to continue
through the end of the work week.

&&

.SHORT TERM...
(This evening through Wednesday)
Issued at 113 PM PDT Tue Apr 23 2024

The orientation of the building trough has continued the feed of
stratus into the area, making for a cloudy day for the Bay Area and
Central Coast. While some of the more inland areas will see the sun
this afternoon, coastal areas will not be so lucky. The afternoon
forecast update delayed clearing times for most areas, with the
coast only seeing a brief late afternoon/early evening period of
thinning clouds. This will also keep areas on the cooler side for
today.

Cloud cover moves inland again ahead of sunset tonight with only
slightly less coverage expected. Drizzle will also be a possibility
overnight once again.

Cloud cover lingers into the afternoon again for Wednesday as the
low pressure and trough combo sluggishly makes its way toward land.
Expect Wednesday afternoon`s temperatures to be underwhelming as
highs along the coast stay around 60 degrees while the more interior
areas approach the upper 60s and lower 70s.

&&

.LONG TERM...
(Wednesday night through next Monday)
Issued at 113 PM PDT Tue Apr 23 2024

Still cloudy and cool with some pockets of drizzle for Thursday and
Friday as the low pressure pushes out of the region to the south and
east. Friday`s model outlook does have a few hints at an earlier
clearing time than the days ahead of it, allowing Friday to be the
start of a modest warming trend.

Yes the preview of May Gray becomes less intense over the weekend as
the new upper level pattern still allows for onshore flow, but with
less aggressive cloud cover. While the immediate coast will continue
to struggle with very persistent cloud cover, most areas slightly
more inland and well into the interior will see quicker clearing
times. This will place most areas back into the 60s and 70s into the
next work week, while the coast will stick to around 60 degree highs.

Model agreement diverges greatly in the longer term forecast. Some
place rain chances back into the forecast for early May, while
others favor more cloudy and drizzly conditions, and others keep the
moisture well to the north. Something to check back in on!

&&

.AVIATION...
(06Z TAFS)
Issued at 1117 PM PDT Tue Apr 23 2024


At this hour, most terminals are VFR but low to mid level clouds
just above the threshold of MVFR CIGs continue to linger over
area terminals. Through the night, cloud cover is expected to
increase, with CIGs lowering to just meet MVFR conditions for most
terminals in the early to mid morning of Wednesday. Cloud CIGs
are at greater altitudes than in previous nights thanks to the
movement of a trough through the region, providing ample lift and
rise. Towards the later morning, CIGs are expected to lift to
usher in VFR conditions, though clouds around 4000-5000` will
persist. Winds out of the W/SW predominantly this afternoon and
breezy between 10-15 knots for most terminals. Terminals near
coastal gaps are likely to see stronger gusts nearing 20 knots. In
the late evening, winds ease below 10 knots and generally become
more westerly. Low clouds return beyond the current TAF period to
bring MVFR conditions once more.


Vicinity of SFO...Currently VFR despite the presence of clouds, but
expected to become MVFR as CIGs lower. Hi-res models show KSFO
seemingly waffling in and out of MVFR CIGs in the mid morning up
until sunrise, with the greatest chances of achieving MVFR around
45% near 14Z. Confidence on MVFR CIG development is low-moderate, so
this will be something that is watched closely through the night.
However, into the late morning and afternoon, high confidence for
VFR CIGs. Winds initially out of the SW and breezy near 12 knots and
gusting up to 20, eventually turning to become more westerly into
the late evening.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR conditions persist through at least the
mid morning of Wednesday, but are expected to become MVFR around 15Z
as CIGs lower. Clearing to VFR expected again into the late morning
and lasting through the remainder of the TAF period. Winds SW in the
afternoon and breezy around 15 knots. Gusts around 20 knots are
likely in the later afternoon. Winds ease into the late night to
below 10 knots.

&&

.MARINE...
(Tonight through next Monday)
Issued at 902 PM PDT Tue Apr 23 2024

A weak low pressure system off the coast will continue to bring
light to moderate southerly winds over the coastal waters. As
this system begin to weaken tonight, northwest flow will return
over the waters ushering in calmer conditions. Moderate swells
will persist through the week.

&&

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

$$

SHORT TERM...Murdock
LONG TERM....Murdock
AVIATION...AC
MARINE...CW

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