Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
321 am PDT Friday Jul 3 2015
Synopsis... drier and turning a little less humid beginning today
and continuing through Sunday as the monsoon flow comes to an
end. Southwest flow aloft next week will bring a seasonal weather
pattern along with a marine layer that will slowly deepen through
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
Coastal stratus is pushing inland early this morning although
bases are quite high...some patchy dense fog will be likely for
some of the higher elevations in the western valleys. With the
somewhat stronger inversion...coastal stratus and patchy fog will
somewhat slow to burn off this morning but should scatter out
before noon except at a few of the beaches where it may remain
cloudy into early afternoon.
Today will be the last day for diurnal cumulus development over
the mountains...with a few cells still possible over the higher
peaks. Southerly environmental flow will cause any cells to be
short lived and drop over the northern slopes of the san Bern
mountains...quickly dissipating...but could cause some brief gusty
winds in the process there.
Thicker coastal stratus will make more inroads into the valleys
late tonight and Saturday morning...and will likely linger through
late Saturday morning.
In the bigger picture...the upper low continues to move slowly
north over the eastern Pacific...about 600 west-southwest from San Diego.
Meanwhile the large subtropical high is still fairly planted over
the southern Great Basin and 4 corners. This pattern is keeping a
broad southerly flow over our area...however the high will
gradually sink to the southeast through the weekend...causing our flow to
become much drier from the SW. With medium range models in pretty
good agreement...the dry pattern will continue through much of
next week with no significant weather makers expected at this time.
Temperatures are expected to be near normal for locations near the
coast and slightly above normal for inland locations...but still
relatively comfortable for this time of year.
030950z...coast/valleys...stratus with bases 800 to 1100 feet mean sea level
spreading 15-20 sm inland through sunrise...reaching ksna by 12z.
Areas of visible 4sm or less where stratus nears higher terrain in the
San Diego County valleys. Stratus clearing 15-17z inland...and by
19z along the coast. Stratus with bases near 1000 feet mean sea level returning
to the coastal airports after 04/03z...spreading 20sm inland
overnight. Otherwise a few clouds at or above 15000 feet mean sea level and unrestricted
visible through Sat morning.
Mtns/deserts...a few cumulus/towering cumulus may develop over the mountain ridges
this afternoon. Otherwise few-scattered clouds at or above 15000 feet mean sea level and
unrestricted visible through Sat morning.
300 am...no hazardous weather is expected through Tuesday.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.