Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA
FXUS66 KMTR 241018
Area Forecast Discussion
National Weather Service San Francisco Bay Area
318 AM PDT Mon Apr 24 2017
.SYNOPSIS...A weak weather system approaching from the northwest
is expected to bring light precipitation to the North Bay this
morning, and may generate scattered showers farther south this
afternoon and evening. Periodic rain chances will continue in the
North Bay through Wednesday, with dry and seasonably cool weather
expected elsewhere. Dry weather along with a warming trend is
forecast across the region from Thursday through the weekend as
high pressure builds in. Locally breezy conditions are likely from
Thursday through Friday.
.DISCUSSION...As of 3:15 AM PDT Monday...Clouds have been on the
increase overnight as a weak weather system approaches from the
northwest. Models show light precipitation developing across
portions of the North Bay from about sunrise through late morning.
Most models also forecast widely scattered light showers south of
the Golden Gate during the afternoon and early evening hours.
Temperatures today will continue to be slightly cooler than
At least two additional weak systems are forecast to move in from
the northwest over the next few days and possibly produce local
light rain at times in the North Bay through Wednesday. From San
Francisco southward look for dry and seasonably cool conditions on
Tuesday and Wednesday.
A more amplified weather pattern is forecast to develop during
the second half of the week, with a deep trough forming over the
Intermountain West while a ridge builds offshore. In between,
across our area, a dry and brisk northerly flow will develop which
will likely result in gusty north winds from Thursday through early
Saturday, especially in the hills. A warming trend will begin on
Friday and continue into the weekend as the upper ridge offshore
edges eastward and over California.
The longer range models diverge somewhat after the weekend. The
GFS maintains a ridge and warm temperatures over California early
next week. The ECMWF retrogrades the ridge offshore, resulting in
some cooling. But both models maintain dry conditions into next
.AVIATION...as of 10:47 PM PDT Sunday...For 06z Tafs. Increasing
mid and high clouds expected through tonight. Moderate and gusty
west winds will continue then diminishing a bit overnight. MVFR
cigs possible over Monterey Bay Area terminals early Monday
morning however confidence is low regarding timing.
Vicinity of KSFO...VFR through much of the period. Confidence is
low regarding a possible return of low cigs Monday morning. West
to southwest winds 15-25 kt anticipated through late tonight with
gusts to 25-30 knots possible. Winds will ease to around 10-15 kt
overnight before ramping up again Monday afternoon.
SFO Bridge Approach...Similar to KSFO.
Monterey Bay Terminals..VFR through much of the period with MVFR
cigs possible overnight into Monday morning. Confidence is low
regarding cigs and timing. West to southwest winds around 10 kt
will ease to around 5 kt overnight before increasing to around 10
kt with gusts to 15-20 kt Monday afternoon.
.MARINE...as of 9:00 PM PDT Sunday...Moderate northwesterly winds
will prevail through much of the forecast period with strongest
winds confined along the coast. Winds and seas will increase
Wednesday and Thursday as high pressure strengthens over the
Eastern Pacific resulting in a tighter pressure gradient across
the coastal waters.
.Tday...SCA...Pt Pinos to Pt Piedras Blancas 0-60 nm
PUBLIC FORECAST: Dykema
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