Increasing onshore flow and a pair of low pressure systems from the northwest will bring a cooling trend through the weekend with stronger and gusty southwest to west winds for the mountains and deserts during the afternoons and evenings through Sunday with gusts to 35 to 45 mph today, and 40 to 50 mph for Friday through Sunday. There is a chance of showers for late Friday into Saturday. A second low pressure system from the northwest will bring additional showers and a slight chance of thunderstorms for late Saturday night through Sunday. Decreasing showers could linger into Sunday night and Monday morning. Then drying and warming through the middle of next week.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
(today through Saturday), A low pressure system will move toward the coast of northern and central California today, then weaken as it moves inland through southern California late Friday and Friday night. Onshore flow will strengthen and spread cooling inland through the weekend.
High temperatures for today will cool a few degrees for inland areas to around 5 degrees for the mountains. Friday high temperatures will be a few degrees cooler near the coast to 4 to 8 degrees for inland areas with similar additional cooling on Saturday. High temperatures of 5 to 10 degrees above average today will cool through Saturday with Saturday high temperatures as much as 5 to 10 degrees below average for the mountains.
High temperatures for today will range from the lower to mid 70s near the coast to the upper 70s and lower 80s for the Inland Empire with the lower deserts in the lower to mid 90s. Following the cooling of today through Saturday, Saturday high temperatures will be mostly in the mid 60s to lower 70s for the coast and valleys with the lower deserts in the upper 70s to mid 80s.
There will be gusty southwest to west winds each afternoon and evening for the mountains and deserts with gusts to 35 to 45 mph today, and 40 to 50 mph on Friday and Saturday.
There is a chance of showers for late Friday into Saturday with rainfall from the coast to the mountains mostly one-tenth inch or less to locally one- quarter inch in the mountains. A snow level above 8000 feet on Friday will lower to 6500 to 7000 feet on Saturday.
(Saturday night through Wednesday), A second stronger and colder low pressure system will move into California on late Saturday through Sunday, possibly lingering into Monday morning. This system is expected to bring more widespread showers and a slight chance of thunderstorms to southwestern California for late Saturday night through Sunday afternoon with rainfall ranging from around one-third inch near the coast to one-half to locally one inch in the mountains with less than one-qaurter inch in the high desert and less than one- tenth inch in the lower deserts. Some additional showers could linger into Sunday night and Monday morning. The snow level will lower to 6000 to 6500 feet on Sunday and 5000 to 5500 feet for late Sunday night into Monday morning.
High temperatures on Sunday will cool another few degrees near the coast to 4 to 8 degrees inland with high temperatures for inland areas mostly 10 to 15 degrees below average to as much as 15 to 20 degrees below average for the mountains above 6000 feet. High temperatures on Sunday will be mostly in the 60s for the coast and valleys with the lower deserts in the 70s. West to northwest winds on Sunday will gust to 40 to 50 mph for the mountains and deserts for the afternoon into the evening.
Then drying with a warming trend through Wednesday with Wednesday high temperatures around 5 degrees above average with high temperatures ranging from around 70 near the coast to the mid 70s to lower 80s for the Inland Empire with the lower deserts in the upper 80s.
091630z, Coasts/Valleys, Areas of low clouds based 900-1400 ft MSL are currently lingering over coastal areas up to 5 miles inland. Remaining low clouds will scatter out by 18z. Low clouds return initially to coastal San Diego County 00-03z Fri with slightly higher bases. Bases slowly continue to rise overnight as clouds expand northward and inland, reaching into the Inland Empire by 09- 12z. Clouds scatter toward the coast again 15-18z.
.Mountains/Deserts, West to southwest winds become elevated again starting 21z Thu-00z Fri with gusts 35-45 kts through passes, along deserts slopes and into the High Desert. Gusts 25-40 kts through the lower deserts. Areas BLDU (vis 3-5SM) expected. Moderate up/downdrafts in lee of mtns. Winds briefly weaken late Friday morning before strengthening again late Friday afternoon.
No hazardous marine conditions are expected through Monday, except for Sunday, when there is a slight chance of thunderstorms along with stronger northwest winds and choppy seas that could generate hazardous conditions.
Ca, None. PZ, None.
