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000
FXUS66 KMTR 061002
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
302 AM PDT Thu Aug 6 2020

.SYNOPSIS...Drizzle is possible in coastal regions Wednesday night
and into Thursday morning. Expect seasonably cool conditions to
persist through Thursday as temperatures slowly adjust toward near
normal for the weekend.

&&

.DISCUSSION...as of 3:04 AM PDT Thursday...A deep marine layer
has persisted over the area after the passage of an upper level
trough on Wednesday. The trough produced drizzle and light rain
over parts of the coast and the hills of Santa Cruz Mountains and
East Bay Hills. Similar conditions are expected in these areas
again this morning but of lighter intensity...measurable amounts
should be no more than a few hundredths.

The Ft Ord Profiler shows the marine layer has weakened due to
cooler air aloft. This will allow the low clouds to mix out late
this morning. Another upper trough will be moving through
the Pacific Northwest today but since it will be much farther
north, temperatures should still rebound from yesterday and be
back to near normal.

After the upper trough moves inland the 500 mb heights rise and
will leads to a warming trend over the weekend. Sunday is expected
to be the warmest day with highs in the mid 60s to low 70s at the
coast to the mid to upper 90s in the warmest inland locations.

Looking ahead in the long-range period...Another trough passing
well north of the area early next week will bring slightly cooler
temperatures but overall the weather pattern will still look like
a typical summer pattern.

 &&

.AVIATION....As of 10:32 PM PDT Wednesday...for 06z TAFs.
Widespread MVFR, with a few pockets in the North Bay with VFR
conditions. Widespread stratus is expected across the region, but
a weak inversion has set up keeping most cigs above 1500 feet
AGL. Cigs should lower slightly, but remain above 1000 feet. There
remains another chance for light drizzle in the early morning
hours, but again mostly closer to the coast. Late clearing on
Thursday morning at most terminals after 18z. Winds have eased
slightly, but remain breezy and onshore. VFR is expected Thursday
afternoon as onshore winds increase. Expect another return of
stratus clouds Thursday evening.

Vicinity of KSFO...MVFR. Most clouds are around 1500 feet
AGL. Clouds will continue to thicken and lower, but low confidence
in having IFR cigs as they are forecast to remain above 1000 feet.
Onshore winds have eased slightly, but remain breezy with
stronger gusts from 20-24 kts. Clouds will break up after 18z for
brief VFR Thursday afternoon with strong onshore winds. Stratus
returns Thursday evening.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals..MVFR with moderate onshore winds. With the
development of an inversion and the previous lower confidence
already, chances for LIFR were removed from the TAFs. The forecast
mainly calls for MVFR cigs, but IFR is possible after 10z, with
clouds lifting after 18z. Cloud cover will remain around the
terminals on Thursday as winds increase in the afternoon with
occasional stronger gusts.

&&

.MARINE...as of 01:52 AM PDT Thursday...Winds continue to be out
of the northwest with stronger gusts, and will prevail across the
waters through the end of the work week.  Expect breezier winds
through the Golden Gate and into the northern San Francisco Bay
toward the Delta on Thursday. These  winds will generate steep
fresh swells resulting in locally  hazardous seas, especially for
smaller vessels. A couple of light  southerly swells will continue
into the weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...Pigeon Pt to Pt Pinos 0-10 nm from 3 PM
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm from 3 PM
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm until 3 AM
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm until 11 AM
             SCA...Pt Reyes to Pigeon Pt 0-10 nm
             SCA...Mry Bay from 3 PM
             SCA...SF Bay from 11 AM

&&

$$

PUBLIC FORECAST: W Pi
AVIATION: DK
MARINE: DK

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