Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
200 PM PDT Friday may 22 2015
Synopsis...a continued trough of low pressure and a deep marine
layer will continue the cool weather through the weekend...with a
few light showers mainly in the late nights and mornings...and areas
of strong gusty winds in the deserts. A warming trend will begin
Monday once the upper low shifts east out of the area. Temperatures
will be back to near normal levels by Wednesday or Thursday with
fair weather prevailing. Night and morning low clouds will continue
in coastal areas next week though.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
The showers have become rather sparse early this afternoon...with
the cool weather continuing as temperatures were mostly below 70 west of
the mountains where it remained mostly cloudy and barely 80 in
warmest parts of the lower deserts.
The upper low will move east through the Colorado River valley this
afternoon. The models indicate a lot of residual moisture over the
weekend under continued troughing. This could bring an isolated
shower again Saturday morning and possibly even Sunday
morning...especially with a more vigorous shortwave moving south
over the Sierra. It looks like the gusty winds in the lower
deserts...especially east of the San Gorgonio Pass...will continue
through Saturday night...so the Wind Advisory will be extended
through late Saturday night. That shortwave moving south over the
Sierra will pass through inland so-cal Sunday and should begin a
change in the weather as the marine layer should get much more
shallow...and ridging will be able to develop behind the trough to
bring a warming trend starting Monday. Temperatures will gradually increase
and may actually be back to normal by Wednesday or
Thursday...possibly even a bit above normal in the deserts. Stratus
will probably be sparse Sunday night with the inversion shift after
the passage of the low...but with onshore flow continuing and the
time of year...the stratus should be moderate common in the nights
and mornings in coastal areas as the week GOES on.
222005z...over and west of the mountains...bkn-ovc cloud decks in
the 2000-8000 feet mean sea level layer with scattered showers in San Diego
County...isolate showers elsewhere...and mountain obscuration. Showers
gradually diminishing through 23/1500 UTC...with cloud decks
becoming broken-overcast in the 2500-6000 feet mean sea level layer. Mountain obscuration
continuing. Slow and partial clearing 23/1500-2000 UTC with maybe an
isolate light shower or two.
High deserts...mostly unrestricted visible through Saturday morning. Broken-
scattered clouds in the 5000-8000 feet mean sea level layer and mostly unrestricted
visible. Clouds gradually diminishing after 23/0900 UTC.
Lower deserts...mostly unrestricted visible through Saturday morning.
Scattered clouds at or above 8000 feet mean sea level with local scattered clouds in the 5000-8000 feet
mean sea level layer. Clouds gradually diminishing after 23/0000 UTC.
West winds 15-25 knots with gusts 30-40 knots over mountain
ridges...through/below passes/canyons...Desert Mountain slopes and into
adjacent desert areas will create moderate-strong uddfs/low level wind shear and possible
rotors over and east of the mountains
105 PM...no hazardous marine weather is expected through Wednesday.
105 PM...long-period swells originating from the South Pacific will
reach the beaches of Southern California late Sunday...Peak Monday
at around 3 feet/16 seconds...and gradually lower Tuesday into
Wednesday. The swells are likely to produce strong rip and longshore
currents late Sunday through Monday...with some elevated surf in
Orange County and northern San Diego County.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
California...Wind Advisory until 2 am PDT Sunday for San Diego County
deserts-San Gorgonio Pass near Banning.