Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
537 PM PDT Tuesday Jul 22 2014
Synopsis...a gradual warming trend is expected to begin on
Thursday and continue into the upcoming weekend as high pressure
builds over the region.
Discussion...as of 02:15 PM PDT Tuesday...the middle/upper level
short-wave that caused elevated convection to develop across the
region this morning is currently moving over the San Francisco Bay
area. As a result...mostly clear skies prevail across the region
this afternoon with a drier air mass aloft. In addition...the
latest Fort Ord profiler shows a very disorganized and mixed out
marine layer in place. Thus...temperatures have warmed nicely so
far this afternoon.
By tonight...the marine layer is forecast to return enough for
some stratus to develop and spread across coastal locations by
Wednesday morning. In the meantime...another weak middle/upper level
disturbance is forecast move across the coastal waters and into
northern California overnight. While chances are too low to
mention in the forecast...cannot rule out a few showers across
our northern coastal waters overnight.
The middle/upper level trough will finally push into the Pacific
northwest Wednesday and bring an end to precipitation chances.
For the remainder of the week...the upper level ridge across the
southwest Continental U.S. Will begin to build westward. This will result in
a warming and drying trend across the Monterey/San Francisco Bay
area through the upcoming weekend and possibly into early next
week.. the warmest conditions will be inland where maximum
temperatures will reach into middle 80s to lower 90s. Near the
coast...daytime temperatures will warm into the upper 60s to lower
Aviation...as of 5:34 PM PDT Tuesday...daytime warmth...residual
monsoonal humidity and weak low level instability is resulting in
some cumulus cloud development around the area. These clouds should
dissipate quickly prior to sunset due to the loss of daytime heating.
The marine layer inversion has dissipated so low cloud development
should be slow to return later this evening and overnight.
Vicinity of ksfo...southwest winds gusting to 20-24 knots until 04z
before settling back below 20 knots. Broken-overcast cloud cover should
dissipate fairly quickly between now and 7 PM. VFR is forecast for
the remainder of the period.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR should hold for well into the
evening. Lower confidence overnight regarding return of low clouds
but for now have gone with VFR.
Marine...as of 02:15 PM PDT Tuesday...light winds over the coastal
waters will continue through tomorrow morning due to a weak
pressure gradient. Tomorrow afternoon northwest winds increase as
high pressure strengthens over the eastern North Pacific.
Public forecast: rgass
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