Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service San Diego California
1051 am PDT Monday Jul 25 2016
thunderstorms are no longer along the beaches of San Diego County
this morning, therefore the beach hazard statement for lightning
was allowed to expire at 10 am. A slight chance of thunderstorms
remains along the coast through this afternoon.
a wave of moist unstable air will bring showers and isolated
thunderstorms this morning to southwestern San Diego County and a
slight chance of thunderstorms in the mountains this afternoon.
High pressure will bring a slow warming trend this week with
coastal clouds nights and mornings. For Friday through next
weekend, an influx of monsoonal moisture will bring cooling for
next weekend, and a slight chance of afternoon and early evening
thunderstorms, mainly near the mountains.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
Previous discussion at 811 am this morning...
we're trying a new flavor of weather this morning. A wave of
unstable air came out of Mexico last night and generated a line of
showers and isolated thunderstorms that skirted the Mexico border
this morning. So far showers were observed in Otay Mesa and
Imperial Beach, but nothing measurable north of the border yet.
Thunder was detected as close as tijuana. This wave is not
resolved well by models and predicting what it will do today is
problematic. Our best analysis indicates isolated light showers
and isolated thunderstorms that could produce very brief heavy
rain mainly south of I-8 in San Diego County this morning.
Meanwhile, there was some coastal low clouds and fog observed,
which was even reported dense at Mission Beach. After the passage
of the wave this morning we will have partly cloudy skies this
afternoon, and a slight chance of showers or thunderstorms, but
only in the mountains. North of San Diego County today's weather
will be more typical, but with more cloud texture to the Sky. High
pressure aloft will slowly build this week over the southwest and
that will continue to feed monsoon moisture skirting our region
mainly just south of the border. That means not as much moisture
Tuesday through Thursday for our region, but you'll see some
higher clouds along with cumulus over the mountains at times. The
marine layer and some coastal cloud coverage will continue each
night and morning. Temperatures inland will inch upward over the
next few days, several degrees above seasonal averages. The
moisture increases just enough Friday to warrant small chances of
showers and thunderstorms in our mountains and deserts that
afternoon and each afternoon through Monday. The high pressure
backs off this coming weekend and that will bring slightly cooler
251745z...coast...-shra will continue over extreme southern San
Diego County and the adjacent coastal waters through late this
morning, with a slight chance of thunderstorms through this
afternoon. Stratus will return to the coastal airports after
26/05z with bases 1000-1500 ft mean sea level.
Valleys/mtns/deserts...isolated ts are possible today, with gusty
winds, strong up/down drafts, small hail and dangerous lightning
expected where storms develop. Conditions will improve by this
a slight chance of thunderstorms with cloud-to-water lightning
will continue across south portions of the coastal waters through
this early afternoon. Otherwise, no hazardous marine weather is
expected this evening through Friday.
a slight chance of thunderstorms will continue along the San Diego
County beaches through this afternoon.
an upper level disturbance moving westward off the northern Baja
Coast will draw mid level monsoonal moisture into far Southern
California with a slight chance of showers and thunderstorms over
southern San Diego County today and the mountains for this
afternoon and evening with a few dry lightning strikes possible.&&
Skywarn activation is not requested. However, weather spotters
are encouraged to report significant weather conditions.