Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
839 PM PDT Wednesday Aug 27 2014
Synopsis...high pressure will persist along the West Coast
maintaining dry weather conditions and near seasonal average
temperatures through the remainder of the week. A weak trough will
then impact the region by late in the weekend...only to cool
Discussion...as of 8:39 PM PDT Wednesday...the final low light
visible satellite image showed low clouds banking against the
coast this evening with clear skies present inland. The Fort Ord
profiler is indicating a marine layer about 2000 feet deep this
evening. However...the 0000z koak sounding is not really showing a
marine layer and is displaying offshore winds from 4000 to 12000
feet. This suggests that low clouds will not make it very far
Today was a warm day around the forecast area with afternoon
temperatures in the middle 80s to middle 90s in land and middle to upper
70s along the coast. Gilroy reached 96 degrees today and Monterey
Airport hit 77 with San Francisco international reporting a high
of 74. Seasonally warm temperatures are expected to persist
through at least the remainder of the week as a ridge of high
pressure resides over California. The current forecast package is
in good shape so no updates are needed at this time.
Previous discussion...as of 1:00 PM PDT Wednesday...upper level
ridge of high pressure will continue to dominate the West Coast
through late week. As a result...a slight warming trend can be
expected over inland areas through at least Friday. Near the
coast...very little change is expected from day to day with
respect to temperatures. However...a modest marine layer is
forecast to return and should bring about more widespread
overnight/early morning low clouds across coastal locations over
the next few days.
By late Friday into Saturday...the forecast models are in good
agreement with pushing the next middle/upper level trough into the
Pacific northwest. This feature will drop southward across our
region through the weekend and cool temperatures down by a few
degrees. In addition...limited moisture from the remnants of
Hurricane Marie is forecast to be advected across the northern
California Friday and Saturday. While precipitation chances remain
very low...can expect at least an increase in middle/high level
clouds through the weekend. Otherwise...seasonal temperatures and
dry weather conditions will continue into the first part of next
Aviation...as of 5:00 PM PDT Wednesday...low clouds along the
coast will move inland once again tonight. Moderate west winds
will ease this evening becoming light and locally variable
overnight. Moderate to high confidence.
Vicinity of ksfo...VFR conditions will persist through late tonight.
MVFR ceilings are expected to return after 09z tonight over koak and
temporarily over ksfo between 11z to 15z. Onshore winds around 15
to 20 knots will ease below 10 knots tonight. Moderate confidence.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR conditions will persist through
late this evening. Borderline IFR/MVFR ceilings are expected to return
after 06z tonight. Onshore winds around 10 to 15 knots will ease
becoming light and variable overnight. Moderate to high confidence.
Marine...as of 1:00 PM PDT Wednesday...southerly swell from
Hurricane Marie will gradually subside through the end of the
week. Mostly light northwest winds will continue over the coastal
waters through Thursday. Winds increase Friday into the weekend.
Southwest swell moves into the waters over the weekend with lower
Public forecast: Larry
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