Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
300 am PDT Friday may 22 2015
Synopsis...a cold upper low moving across Southern California will
bring scattered showers today. A thunderstorm is also possible. A
few light showers could linger into Saturday morning. It will
continue windy in areas of the mountains and deserts through this
evening. A deep marine layer will continue the cool weather through
the weekend...but it will be warmer on the Holiday. Fair and
seasonal weather is expected next week.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
Scattered showers have developed and moved ashore especially in
northern San Diego County early this morning. A couple spots have
received a tenth inch...but in many areas nothing measurable yet.
The the best wave of showers will move through the region between 5
and 9 am this morning...and that is also when our atmosphere is at
its most unstable and capable of producing a thunderstorm or two.
The showers seem to be following a path more directly through San
Diego County. Snowfall is almost not Worth mentioning...with only up
to an inch possible above 6500 feet elevation. Showers will taper
off during the day. Winds in parts of the deserts will diminish just
a little this morning...but will come back strong this afternoon and
early evening. Our compact and potent low pressure trough will move
out of the region later today and Saturday. However...enough
cyclonic flow and residual moisture remains to mention a very slight
chance of showers through Saturday morning...mainly in San Diego
County. Another shortwave trough moves through Nevada and eastern
California on Sunday which will maintain a healthy marine layer and
plenty of night and morning clouds in the coastal basin. Memorial
Day will present some noticeably warmer weather and more sunshine.
Tuesday and beyond...a weak ridge and trough pattern sets up. That
means fair and seasonal weather with minor variations in extent of
the coastal low clouds during the nights and mornings.
220900z...bkn-ovc low clouds over and west/of the mountains...with bases
2500-4500 feet mean sea level and tops to 9000 feet mean sea level will continue through this
evening. Isolated thunderstorms will be possible this morning...mainly over
San Diego County. Ceilings and visible will lower at times during
showers. Conditions will improve this afternoon...with scattered/broken low clouds
continuing over and west of the mountains through tonight.
West winds with gusts to 45 knots will continue to bring moderate-strong
uddfs/low level wind shear over and east of the mountains through this evening.
200 am...isolated thunderstorms are possible over the coastal waters
this morning as a low pressure system moves across the region. See
the marine weather statement for details. Otherwise...no hazardous
marine weather is expected through Tuesday.
200 am...long-period south swells arriving late Sunday will peak
Monday at 3 feet/16 seconds...and gradually subside Tuesday into
Wednesday. These swells will likely produce strong rip and longshore
currents late Sunday through Monday...with some elevated surf on
exposed south-facing beaches.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
California...Wind Advisory until 9 PM PDT this evening for San Diego County
deserts-San Gorgonio Pass near Banning.