Scientific Forecaster Discussion
Southwest California area forecast discussion
National Weather Service Los Angeles/Oxnard California
200 am PDT Friday Jul 3 2015
through the Holiday weekend...a slight cooling trend is
expected along with a gradual increase in night and morning low
clouds and fog across the coastal plain and valleys. For next week
an upper low will slowly approach the West Coast...resulting in
continued night and morning low clouds and fog as well as seasonable
Short term (today-sun)...overall...00z models in good synoptic
agreement through the period. At upper levels...low will spin about
600-700 miles west of Point Conception through the weekend. Near the
surface...moderate onshore flow will prevail.
Forecast-wise...rather typical and benign forecast on tap for the
Holiday weekend. Southerly flow aloft around the upper low will keep
any monsoonal moisture east of the area. Therefore...focus will be
on typical summertime marine layer stratus.
Latest amdar soundings indicate marine inversion based around 1000
feet this morning...with stratus along the coast. Do not anticipate
much inland push this morning...so stratus should generally remain
confined to the coastal plain...although some stratus will be likely
across the Santa Ynez Valley and into the San Gabriel valley.
Stratus and fog should dissipate nicely by afternoon with mostly
sunny afternoon skies for all areas. Afternoon highs today will be a
bit cooler especially west of the mountains.
For tonight/Saturday...marine inversion is expected to deepen with
stratus pushing into the coastal valleys overnight. By Saturday
afternoon will expect stratus to dissipate...with a mostly sunny
afternoon. Temperatures on Saturday will exhibit a slight cooling
trend from today.
For Saturday night/Sunday...expect a nearly persistent pattern with
respect to the inland extent of marine layer stratus...and slightly
cooler temperatures Sunday afternoon. For fireworks shows Saturday
evening...inland areas should be clear...but locales near the
beaches have a chance to be cloudy.
Long term (mon-thu)...for the extended...models continue to exhibit
good synoptic agreement. At upper levels...previously mentioned low
off of Point Conception will slowly work its way northeastward into
northern California. Near the surface...moderate onshore flow will
Forecast-wise...main challenges will continue to be the marine layer
stratus as southwesterly flow aloft keeps the area dry. Stratus will
likely Ebb and flow through the week...but should be able to push
into most valley areas each night/morning. Afternoon high
temperatures will exhibit a slight cooling trend...but should hover
near or a few degrees below seasonal normals. Just typical
summertime weather for the district.
Will be updated with 12z taf package.
Will be updated shortly.