High temperatures will remain as much as 5 to 10 degrees below average for the mountains and inland valleys today. High temperatures will warm slightly for Friday and a few to around 5 degrees on Saturday, then cool a few degrees each for Sunday and Monday. A warming trend will begin next Tuesday with high temperatures returning to around average on Wednesday. Night and morning coastal low clouds will spread inland across much of the valleys into this morning, then not as far into the valleys the following nights as the marine layer becomes shallower.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
, UPDATED AVIATION DISCUSSION,
(today through Saturday), A low pressure system centered across northern California will maintain high temperatures as much as 5 to 10 degrees below average for the inland valleys today. The low pressure system will move inland on Friday with weak high pressure moving across California on Saturday. High temperatures on Friday will warm a degree or two, then a few to around 5 degrees on Saturday with the greatest warming for the valleys into the mountains. High temperatures on Saturday will still be a few degrees below average with high temperatures ranging from the 70s near the coast to the mid 80s to lower 90s for the Inland Empire with 100 to 104 for the lower deserts.
The marine layer is around 3500 feet deep with coastal low clouds spreading into much of the valleys into this morning. The marine layer will become gradually shallower for tonight into the weekend with night and morning coastal low clouds not spreading as far into the valleys for early Friday and only into the far western valleys for early Saturday.
(Sunday through Wednesday), A weak low pressure system off the California coast on Saturday will move slowly inland into California on Sunday and Monday with not much change in high temperatures on Sunday. Monday high temperatures will cool a few to around 5 degrees. High pressure to the east will bring warming for Tuesday and Wednesday.
High temperatures on Monday will be as much as 4 to 8 degrees below average for the valleys into the mountains with high temperatures on Monday ranging from the lower to mid 70s near the coast to the lower to mid 80s for the Inland Empire with the upper 90s for the lower deserts.
High temperatures on Wednesday will warm to within a few degrees of average with the high temperatures ranging from the mid to upper 70s near the coast to the upper 80s to mid 90s for the Inland Empire with the lower deserts around 100.
171130z, Coast/Valleys, Low clouds around 2800-3500 feet MSL fill the coastal basin this morning. Some foothills obscured in clouds and FG. Scatter out by 17-19Z. Low clouds based around 2000-3000 feet MSL will return to KSAN and KCRQ by 23-03Z before spreading north and into the entire coastal basin by 12Z Friday.
Mountains/Deserts, Mostly clear and VFR conditions today and tonight.
No hazardous marine conditions are expected through Monday.
Ca, None. PZ, None.
