Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA
FXUS66 KMTR 241548
Area Forecast Discussion
National Weather Service San Francisco Bay Area
848 AM PDT TUE MAY 24 2016
.SYNOPSIS...A weak low pressure system will bring a slight chance
of showers and a thunderstorm or two to our region today.
Temperatures will be seasonably cool, but gradually warm later in
.DISCUSSION...as of 8:45 AM PDT Tuesday...Widespread cloud cover
over the region this morning with temperatures generally in the
50s. Meanwhile, a long wave trough extends down the Pacific
Northwest into northern and central California. Increased moisture
and weak disturbances riding along the trough will result in
chances for showers and thunderstorms over a portion of the region
again this afternoon. Have updated the ongoing forecast to
included convection over the Santa Lucia Mountains for this
afternoon along with the North and East Bay Hills/Mountains and
the higher terrain of San Benito County. Otherwise, cooler than
average temperatures expected for the remainder of the day with
most locations only warming into the 60s to lower 70s.
Note: Current visibility sensor at KSNS (Salinas Airport) has been
inaccurate since Monday morning. NWS Technicians are on site
looking into the problem this morning.
.PREVIOUS DISCUSSION...as of 3:30 AM PDT Tuesday...Widespread
clouds this morning across most of our CWA with a onshore west-to-
east gradient of 1.5 MB. Synoptically, a longwave trof extending
from Central Canada remains across our entire region. Similar to
yesterday a weak impulse will move through our cwa today and
likely trigger a few showers. Lifted values are forecast to drop
to below zero values over parts of the North Bay plus eastern
sections of the CWA, therefore still looks like a slight chance of
thunderstorms. The pattern also favors small hail with any of the
cells. The trof will start to progress to the east by Wednesday
afternoon which will effectively bring an end of precipitation.
Our string of cooler than normal conditions will continue through
at least Wednesday with many spots in the 60s to lower 70s. As a
ridge starts to build back starting on Thursday, temperatures will
warm back closer to normal values. That trend will continue into
weekend with the range in the mid 60s to the upper 70s. A few
lower 80s cannot be ruled out for far southern and eastern
Longer range outlook favors warmer than normal conditions next
week with mostly dry conditions.
.AVIATION...as of 04:55 AM PDT Tuesday... Marine stratus
infiltrating coastal and inland valleys this morning as upper
trough looms aloft. Marine stratus will linger until 17-18Z
timeframe for most locations. Drizzle along coast possible this
morning. A few light showers are also possible throughout the day
with wrap around energy and moisture. Onshore winds generally 16
kt or less, increasing Wednesday afternoon. MVFR cigs return
Vicinity of KSFO...MVFR through 17-18z timeframe, then vfr.
Onshore winds up to 15 kt this afternoon. MVFR returns after 04z
SFO Bridge Approach...Similar to KSFO.
Monterey Bay Terminals...MVFR cigs with drizzle through 18z, then
VFR with partly to mostly cloudy skies lingering through the
afternoon. Onshore winds generally 12 kt or less, with occasional
gusts through the afternoon. Light rain showers possible through
the day. MVFR cigs return this evening.
.MARINE...as of 08:43 AM PDT Tuesday...Light to moderate winds and
small seas will persist today. Winds will increase tonight and
Wednesday as high pressure builds over the region. The winds will
be strongest north of Point Reyes.
PUBLIC FORECAST: RGass
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