Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA
FXUS66 KMTR 271749
Area Forecast Discussion
National Weather Service San Francisco Bay Area
1049 AM PDT MON JUN 27 2016
.SYNOPSIS...Typical summer weather is expected to continue with
very warm temperatures for inland spots and cool temperatures
near the coast. Some cooling is anticipated around the forecast
area for the second half of the week as a weak system to the
north moves near our region. The outlook for the Fourth of July
holiday weekend calls for dry weather along with gradual warming.
.DISCUSSION...as of 09:16 AM PDT Monday...Generally quiet weather
conditions prevail this morning a shallow marine layer in place.
This has resulted in low clouds near the coast that should
mainly remain confined to near the coast or over the coastal
waters through this afternoon. Meanwhile, inland areas are rapidly
warming with low to mid 70s reported at this hour with some 80s in
the hills. Do expect light onshore winds to keep coastal areas
cool today with widespread 90s inland with a few of the warmest
locations breaking the 100 degree mark again this afternoon.
The ongoing forecast remains on track and no major updates are
needed at this time. Please see the previous discussion below for
.PREV DISCUSSION...As of 3:00 AM PDT Monday...Satellite overnight
shows area of clouds just off the coast with a few coastal
locations now seeing patchy fog. Thanks to the surface gradient
more than 3 MB from west to east some of the clouds should make it
to more coastal spots. The marine layer has compressed to around
500 feet so generally little inland push is forecast. Highs today
will be the same or even a few degrees warmer than Sunday as the
ridge of high pressure across the southern half of the US expands
a bit to the north and west. 500 MB heights will increase to
around 593 DM by afternoon (increase of 1 DM) while 925 temps will
warm an additional degree.
Highs will be in the 60s and 70s at the coast with 80s and 90s
for most inland communities. Far interior areas will be in the 95
to 105 range. Heat impact levels indicate the worst impact will be
in sparsely populated southern Monterey County while urban
locations will generally be in the slight risk. Tuesday will be
very similar to today as the synoptic pattern is a virtual repeat.
The ridge will slightly flatten starting on Wednesday and 925 MB
temps will gradually drop as a weak system passes to our north the
second half of the week. Coastal spots will see only minor changes
while far inland areas will drop 10 to 17 degrees by Saturday. On
that day Napa Count will just have upper 70s to lower 90s instead
of the 90s to lower 100s.
The ridge will build back to our region next work week helping to
boost inland highs back to very warm levels. Still looks like a
very warm and dry Fourth of July.
.AVIATION...As of 10:49 AM PDT Monday...Strong mid-upper level
high persists over the area. Areas of low cigs/vsbys at the
immediate coast due to fog and stratus, otherwise VFR.
Vicinity of KSFO...Gusty west winds to around 30 kt 22z-04z.
SFO Bridge Approach...Similar to KSFO.
Monterey Bay Terminals...Very shallow cigs are mixing out, VFR
forecast for this afternoon and early evening. Low cigs to return
.MARINE...as of 09:16 AM PDT Monday...Gusty northwest winds will
continue over the waters today with a tight surface pressure
gradient in place. The gusty northerly winds will produce squared
seas while a longer period southerly swell moves through as well.
The strong winds are forecast to last at least through the end of
.Tday...SCA...Pigeon Pt to Pt Pinos 0-10 nm
SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm
SCA...Pt Arena to Pt Reyes 0-10 nm
SCA...Pt Reyes to Pigeon Pt 0-10 nm
SCA...Pt Arena to Pigeon Pt 10-60 nm
SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm
SCA...Mry Bay from 3 PM
SCA...SF Bay from 3 PM
PUBLIC FORECAST: RGass
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