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fxus66 kmtr 162144 
afdmtr

Area forecast discussion
National Weather Service San Francisco Bay area
144 PM PST Sat Nov 16 2019

Synopsis...a gradual warming and drying trend will continue through
the remainder of the weekend as high pressure builds over the
region. Cooler conditions will develop on Tuesday as a frontal
boundary sweeps through the region and low pressure develops to our
south. Mainly dry weather conditions are likely to persist with
seasonable temperatures through the second half of the upcoming
week.

&&

Discussion...as of 01:41 PM PST Saturday...low clouds and fog
have mostly dissipated across inland areas of the region by early
this afternoon. However, visible satellite and surface
observations low clouds and fog continue to impact portions of the
coastal areas as well as around the San Francisco Bay reducing
visibility to 1sm or less at times. Look for gradual improvement
in these areas as well through early afternoon as surface
temperatures warm and drier air aloft mix down to the surface.
With this, look for temperatures in the Lower/Middle 60s at the
coast with widespread 70s inland through the remainder of the
afternoon.

Currently expecting less widespread cloud cover and/or fog tonight
as boundary layer conditions dry out a bit in response to the
mid/upper level ridge aloft. In addition, daytime temperatures will
warm a bit on Sunday with more widespread 80s across the interior
and 70s near the coast. These values will be as much as 10 to 15
degrees above seasonal averages. Conditions may only cool slightly
on Monday, most notably at the cast, as the aforementioned ridge
begins to weaken ahead of an approaching upper level trough.

More widespread cooling is forecast by Tuesday lasting into midweek
as an upper level trough over the Pacific northwest drops southward
over California. The forecast models generally agree this system
will pass through the region with very little to no precipitation at
all. As the system drops southward, it is forecast to develop into a
closed low pressure center near/off of the Southern California
coast. At this point, the system will tap into deeper moisture and
potentially result in widespread precipitation over Southern
California. However, there remain differences in the forecast models
on the exact timing and placement of the aforementioned system.
Thus, confidence remains low at this time. The European model (ecmwf) solution shows
the most Promise for precipitation over the central coast, yet even
the ensembles show only a few hundredths of an inch or so from
Wednesday into Thursday. Periods of dry offshore flow may also
develop in the hills in the Wednesday and Thursday timeframe
resulting in heighten fire weather concerns. This is something that
will be monitored in the coming days.

Seasonably cool temperatures are then likely to persist for late
next week into next weekend with mostly clear/sunny conditions.
Aside from the non-zero chance of precipitation mentioned above, dry
weather conditions are likely for the remainder of the forecast
period.

&&

Aviation...as of 11:20 am PST Saturday...for 18z tafs. A very
compressed marine layer exists along the coast and over the bays,
with associated low clouds and fog having resulted in very
restricted ceilings and visibilities earlier this morning. Both
are progressively improving, with VFR conditions now having
returned to all terminals except ksfo and koak. During the first
part of the afternoon these too are expected to clear. VFR
conditions and light winds are then forecast to prevail through
at least mid evening, though patches of low clouds and fog will
remain.

Vicinity of ksfo...vlifr conditions continue at present, but with
gradual improvement expected to begin soon. Clearing anticipated
between 20-21z, then VFR this afternoon through the late evening
hours. Seabreeze winds less than 15 kt beginning during the
afternoon.

Sfo bridge approach...similar to ksfo.

Monterey Bay terminals...VFR conditions have now returned to both
terminals and are expected to continue through at least early
evening. Onshore winds 5-10 kt during the afternoon.

&&

Marine...as of 8:57 am PST Saturday...breezy northwest winds
are expected to develop today, then diminish a bit later tonight
through Sunday except over the far northern waters. A relatively
large, moderate period northwest swell will continue through the
day today, producing hazardous conditions for small crafts. The
swell will begin to subside on Sunday. Moderately strong and gusty
northwest winds are forecast to arrive beginning late Monday
night and a larger northwest swell beginning Tuesday night.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 0-10 nm until 9 PM
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm until 9 PM
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm until 9 PM
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm until 9 PM
Small Craft Advisory...Pigeon pt to pt Piedras Blancas 10-60 nm until 9 PM
Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm

&&

$$

Public forecast: rgass
aviation: blier
marine: blier

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