Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
845 PM PDT Thursday Aug 21 2014
thunderstorms have ended this evening...and low pressure aloft will
continue to move east out of the area and result in a return to fair
weather the rest of tonight with areas of low clouds near the coast.
Fair weather will prevail Friday through the middle of next
week...with areas of coastal low clouds and local fog during the
nights and mornings. Temperatures will stay a little below seasonal
normals through the weekend...then increase to a little above normal
by the middle of next week.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
More action occurred today due to the thunderstorms in the mountains
and deserts producing local flooding...and the strong outflow from
the Imperial County complex which produced widespread blowing dust
and local near-zero visibility in the Coachella Valley between 4 and
6 PM...plus 3 wind gusts in the 46-48 miles per hour range there. That outflow
intersected with the sea breeze over the San Diego County mountains
after 6 PM to produce one last line of vigorous thunderstorms
there...but that dissipated by 730 PM. Now...the upper low that
brought the action of the past 2 days is over Yuma as is continuing
to move east. Marine inversion base is around 1500 feet...with
inversion strength around 4 degree c...so there will be areas of
stratus near the coast overnight.
Fair weather will prevail Friday through at least the middle of next
week. There will be mean troughing over the western US Friday
through Sunday...so that will help keep temperatures a little below
normal...with mostly 80s to near 90 in the valleys and near or just
below 100 in the lower deserts for highs. Tropical systems moving by
well to the south will contribute to some middle-level moisture over
our area...mainly as we go into next week...though most of that will
stay just to our south...so thunderstorm chances will be quite low
for awhile. High pressure aloft will rebuild early next week and
peak sometime around Wednesday for increasing temperatures...though models
vary in the details such as where the center of the high pressure
aloft will be which would have an effect on temperatures and depth
of the marine layer. Models indicate the high might weaken a little
late next week as a trough or at least broad westerlies affect the
220300z...debris clouds at or above 10000 feet mean sea level from earlier
thunderstorms will continue to drift around but gradually clear
overnight. Low clouds along the coast will develop and move into
coastal airports between 06-11z. Bases will be around 1200 feet mean sea level
with tops to 2200 feet. Scatter out on Friday expected by 16-17z.
Otherwise mostly clear Friday with only a few cumulus over mountains.
100 PM...no marine weather hazards are expected through Tuesday.
southerly swell will create higher than average surf and strong rip
currents at the beaches through this weekend. Highest surf sets to
7-8 feet are expected in Orange County and strong longshore currents
will occur in San Diego County. A beach hazards statement is in
effect through Sunday afternoon...see laxcfwsgx.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
beach hazards statement through Sunday afternoon for the Orange
County coastal areas and San Diego County coastal areas.