Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA
FXUS66 KMTR 281751
Area Forecast Discussion
National Weather Service San Francisco Bay Area
1051 AM PDT THU JUL 28 2016
.SYNOPSIS...Very warm conditions will persist inland through the
remainder of the week as high pressure remains over the west.
Meanwhile, cooler temperatures will continue near the coast as a
result of weak onshore flow. Slight cooling is expected over the
weekend as an upper level trough develops off of the Pacific
.DISCUSSION...as of 09:39 AM PDT Thursday...Slightly more defined
marine layer this morning, around 1000 feet in depth, allowed for
low clouds to push inland across San Francisco, into the East Bay
and North Bay Valleys. In addition, low clouds and patchy fog was
observed in and around the Monterey Bay Region, locally into
the northern Salinas Valley. The cloud deck has now mostly
retreated to the coast as inland temperatures begin to warm. Made
just a few adjustments to the forecast to reflect current sky
cover based off satellite trends. Otherwise, the ongoing forecast
for today remains on track.
.PREV DISCUSSION...as of 3:15 AM PDT Thursday...Low clouds have
filled in solidly along the coast from Seattle south to Point
Conception. The marine layer depth remains shallow, around 1000
feet per the Fort Ord profiler, but an onshore flow has pushed the
stratus into the Salinas Valley as well as portions of the North
Bay Valleys. Satellite fog product is also showing some high
clouds currently developing over the central third of the cwa,
from San Benito county north into the South and East Bay. Still
keeping an eye on increasing mid and upper level moisture
spreading north into Central and Northern California.
Meanwhile, the high pressure ridge that has built into Southern
and Central California from the Desert Southwest, will continue to
bring hot temperatures to inland areas today with high
temperatures expected to be only slightly less hot than those on
Wednesday, ranging from the 80s to around 100 in the warmest
areas. Near-coastal locations will continue to be mainly in the
60s, cooled by the marine influence and onshore flow. Similar
conditions are expected on Friday.
By Saturday, an approaching upper level trough will being to bring
some cooler air into the area with high temperatures across inland
areas cooling by 5 to 10 degrees over the weekend. Coastal areas
will still see highs mainly in the 60s. The cooling trend will
then continue into next week.
.AVIATION...as of 10:50 AM PDT Thursday... Soberanes fire smoke is
less concentrated around the region this morning... leading to
improved visibilities and ceilings versus previous few mornings.
A compressed marine layer did nudge itself slightly inland last
night and lead to very low ceilings/visibilities, especially when
combined with any lingering smoke around the Monterey Bay region.
The marine layer has now retreated and widespread VFR is now being
reported across all TAF sites. Expect a similar early return of
VLIFR along the immediate coast by 03-04Z. Smoke plume is expected
to be thickest southeast of the Soberanes fire today.
Vicinity of KSFO...VFR with onshore winds AOA 15KT. MVFR/IFR cigs
posbl around sunrise tomorrow.
SFO Bridge Approach...Similar to KSFO.
Monterey Bay Terminals...VFR with several layers of lingering
smoke from 3000 and above this morning. Bulk of smoke should be
aimed away from KMRY but some will infiltrate the airport into the
afternoon. Early return of VLIFR-LIFR cigs/visbys by 03/04Z posbl.
.FIRE WEATHER...as of 3:15 AM PDT Thursday...Warm and dry
conditions will continue through Friday, especially at elevations
above 1500 feet as high pressure remains over the area. Weak
onshore flow will persist along the coast with light and variable
to light southerly winds over the Santa Lucia Mountains and Los
Padres National Forest through the morning, becoming westerly by the
afternoon. Winds aloft will remain out of the south which will
transport the smoke associated with the Soberanes Fire to the
north over the Monterey Bay and across the Bay Area. Warm and dry
conditions will continue to impact firefighting efforts into the
.MARINE...as of 09:39 AM PDT Thursday...North winds will continue
over the coastal waters today. winds will be strongest over the
northern outer waters and north of the bay bridge. a mixed swell
will continue in the coastal waters. a longer period southwest
swell arrives later in the week as a tropical storm weakens.
SCA...Pt Arena to Pigeon Pt 10-60 nm
PUBLIC FORECAST: RGass
FIRE WEATHER: Sims
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