Isolated light showers west of the mountains tonight along with decreasing west winds in the mountains and deserts. Warmer early this week, then minor cooling and a slight chance of precipitation towards the middle of the week. Warmer and drier for the end of the week.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
Evening update, No precipitation is evident on radar or gauges this evening. A secondary short wave is dropping south to near Point Conception and will move into So Cal tonight into Monday morning. This will produce another round of isolated light showers along and west of the mountains. Additional rainfall accumulation is expected to be around 0.10" or less, and many locations may receive none. The snow level will fall to around 5500 ft with any accumulation less than one inch. Otherwise breezy west winds in the mountains and deserts weaken overnight. Monday remains cool with high temperatures as much as 10-15 degrees below normal inland, and around 3-8 degrees below normal closer to the coast.
Previous discussion, Fair weather with a warming trend will begin on Tuesday and continue through Wednesday as a low pressure system moves south out of the Gulf of Alaska and a weak ridge of high pressure develops over the Desert Southwest. Wednesday will likely be the warmest day with temperatures ranging from a few degrees below to a few degrees above seasonal averages.
Numerical models have adjusted solutions to slow down the progress of the Gulf of AK low so that it doesn't move into SoCal/northern Baja until Thursday. This means that we're unlikely to see any precipitation from this system until late Wednesday/early Thursday. Models are in pretty good agreement through Thursday with respect to the synoptic pattern, showing the closed upper low moving over northern Baja late Thursday. This trajectory could bring us precip on Thursday but not much in the way of winds or cold air. Temperatures on Thursday will likely be generally near or a little below seasonal averages.
Dry and warmer for Friday and Saturday under a transient ridge of high pressure between the departing system moving into the southern Rockies and another low pressure system moving in from the northwest.
270600z. Coast/Valleys, VFR conditions widely scattered clouds around 4500-5500ft MSL. Another round of VCSH is set to move through the coastal basin through the overnight hours. Any showers will be fairly light and provide little to not impact to any TAF sites before eventually clearing out by 18z. Cumulus based around 3000ft MSL forming Monday morning become less numerous after 18z Monday.
.Mountains/Deserts, Gusty west winds with surface speeds up to 15- 25 kts, locally higher through mountain passes and near ridgelines, dying down by 12z Monday Mod to strong up/downdrafts near peaks and on desert slopes. Periodic reduced VIS due to BLDU. Similar westerly gusts up to 20 kts expected to pick back up after 21z Monday.
No hazardous marine conditions are expected through Thursday.
Ca, Wind Advisory until 2 AM PDT Monday for Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts-San Gorgonio Pass near Banning.
PZ, None.
