Light showers will continue to move through the area tonight. Cooler with gusty onshore winds in the mountains and deserts through Thursday, with the strongest winds Wednesday afternoon into Wednesday night. Weak offshore develops for Friday and Saturday for drier weather and locally gusty northeast to east winds below the passes and canyons. This will be followed by warming through next weekend with high temperatures warming to 10 to 15 degrees above average for next Sunday. Brief cooling Monday followed by minor warming again on Tuesday.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
Evening update, Light showers are moving into So Cal this evening, mainly north of San Diego County. So far most of the measurable precipitation has been in the mountains and high desert, and accumulations have been less than 0.10 inch. Additional accumulation tonight will generally be less than 0.10 inch for the coasts and valleys, with the potential for some locations to not measure at all, another few hundredths to around 0.25 inch in the mountains, and 0.05 inch or less in the deserts. The upper level trough currently moving through Central CA will quickly move out by Wednesday morning, ending our precipitation chances. Snow levels will fall to around 7000-7500 ft by Wednesday morning though any accumulations will be less than one inch. Otherwise west winds gusting to around 35-50 mph will continue across the mountains and deserts into Thursday. High temperatures will be around 3-5 degrees below normal Wednesday and Thursday.
Previous discussion, A stronger low pressure system currently in the Gulf of Alaska will move inland over WA/OR Wed-Thu, reaching the northern Rockies by Friday. A sfc high will follow the low into the Great Basin producing offshore flow for Fri and Sat. Northeast to east winds begin to develop Friday morning and weaken on Saturday. The strength of the Santa Ana winds is still uncertain but with no upper level support, it will likely be relatively weak. North to northeast winds gusting to 25 to 35 mph along and below the coastal slopes of the mountains are expected on Friday. Conditions will trend warmer for Friday through Sunday. High temperatures on Sunday will be around 10 to 15 degrees above average ranging from the 70s near the coast to mid 80s to lower 90s for the Inland Empire with the lower deserts in the 90s.
Weak onshore flow will return for Monday and Tuesday, bringing cooler conditions to the coast and valleys. Elsewhere, temperatures will remain relatively unchanged.
010500z, Coast/Valleys, This evening there are layers of cloud bases: prevailing cigs are 3-9 kft MSL with patchy MVFR bases. SCT -RA/SHRA continue to develop across the basin from northwest to southeast, bringing brief periods of MVFR cigs/vis and even an occasional IFR cig/vis. Rain activity to taper off around 12z early Wed, though ISO -SHRA to linger in the foothills through 16z.
Clouds scatter out 16-18z, mostly in the lowlands and partially in the foothills (bases 3-5kft MSL). Low clouds fill in once again gradually after 00z throughout the coastal basin with bases 2500- 3500 ft MSL.
Mountains/deserts, Clouds intersecting terrain to lower vis 0-5SM through 16-18z Wed. Layered bases up to 12 kft MSL. SHRA/+SHRA in the mountains through 14z, especially in the San Bernardino County mountains. Strong westerly winds 35-45 mph gusts 55 mph over mountain ridges, desert slopes and locally into deserts this evening into Wednesday; gusts near 30 kts possible VCTY KPSP/KTRM. MOD up/downdrafts in lee of mountains, and areas of vis reduced to 2-5SM in BLDU in deserts.
No hazardous marine conditions expected through Wednesday. Northwest winds 20 to 25 knots late Thursday in the outer waters.
Ca, Wind Advisory until 11 PM PDT Thursday for Apple and Lucerne Valleys-Coachella Valley-Riverside County Mountains-San Bernardino County Mountains-San Diego County Deserts-San Diego County Mountains-San Gorgonio Pass near Banning.
PZ, None.
