Scientific Forecaster Discussion
fxus66 ksgx 221112
Area forecast discussion
National Weather Service San Diego California
412 am PDT Thu Aug 22 2019
a weak trough of low pressure will spread cooling inland through
Friday. The marine layer will deepen into Friday with low clouds
and locally dense fog near the coast this morning, spreading into
the far western valleys for tonight into Friday morning. The
marine layer will become slightly shallower for the weekend into
next week with night and morning coastal low clouds spreading into
the far western valleys. High pressure across California will
bring warming for areas west of the mountains during the weekend
with minor day today changes into next week. For areas farther
inland, monsoonal moisture will bring an increase in humidity with
warmer nights and not much change in high temperatures. There
will be some high clouds at times and some afternoon clouds near
the mountains, but chances for afternoon thunder near the
mountains are still small.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
A trough of low pressure will move inland through the Great Basin
today and into the northern and central rockies on Friday. This
will spread cooling inland through Friday. A coastal eddy has
developed and will continue into Friday. Satellite imagery shows
more widespread low clouds over the coastal waters extending
inland to about Interstate 5 in Orange County and The Mesas in San
Diego. Fog will be locally dense early this morning near higher
coastal terrain inland to The Mesas.
The fog will clear back toward the coast during the morning
between 8 am and 10 am, but the marine layer will continue to
deepen for today and tonight. Low clouds and fog will spread back
inland tonight into Friday morning with lowest visibility tonight
and early Friday morning in the western valleys in San Diego
For the weekend, high pressure over the eastern Pacific will
expand across California. The marine layer will become a little
shallower with high temperatures west of the mountains warming to
slightly above average during the weekend with not much change
during the early and middle part of next week.
Some monsoonal moisture will return for the weekend into next
week. This will bring an increase in humidity for inland areas
with warmer nights and with high temperatures not changing much.
There will be some high clouds at times and some afternoon clouds
near the mountains. The moisture increase and vertical
distribution of the moisture may not be sufficient for afternoon
thunder. But if thunder were to occur, it would be most likely
near the mountains each afternoon beginning on Sunday.
220900z...coast/valleys...areas of stratus with bases 300-800 ft mean sea level
filling in along the coast and spreading locally up to 15 miles
inland this morning. Areas of vis 3-5 sm in br, with local vis 1 sm
or less in fog over higher coastal terrain, including at kcrq.
Stratus and vis restrictions clearing to the coast 15-18z. Stratus
moving back inland 23/00-03z with bases 600-1100 ft msl, moving 10-
15 mi inland overnight.
Mountains/deserts...mostly clear with unrestricted visibility
through Friday morning.
no hazardous marine conditions are expected through Monday.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.