Dry and warmer weather, with marine layer low clouds each night and morning in the coastal areas and valleys, will follow through most of next week. The marine layer deepens and temperatures begin to cool a little as we approach next weekend. Another low pressure system will bring unseasonably cool and windy conditions for next weekend into next Monday, with chances for showers on Sunday.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
This morning, The marine layer remains about 4,000 ft deep with most of the low clouds pushed up against the coastal mtn slopes and foothills. Low cloud coverage is spreading toward the coast, and high-resolution models show most of the region west of the mtns covered by low clouds before about 6 am.
California remains under the influence of broad upper level troughing extending to the southwest from a closed upper low currently centered over Utah. Numerical model guidance remains in good agreement through Wednesday, showing a trough of low pressure over SoCal through Tuesday followed by a weak, transient high pressure ridge on Wednesday. The cold airmass that moved in from the northwest over the last few days will gradually modify through Friday. A warming trend begins today, and current guidance shows Tue and Wed as the warmest days of the week. Daytime temps on Tue and Wed will reach the upper 70s in the inland valleys, and the low 90s in the lower deserts.
For the latter half of the workweek, there is greater spread among model solutions as a weak low pressure system moves into SoCal, but this results in only slight lowering of temperatures. The inland valleys will still see high temps in the 70s and the low deserts will still see daytime high temps near 90 degrees.
The marine layer will remain relatively deep for today through Friday with minor day-to-day variations in the low cloud coverage west of the mtns.
For next weekend, Model guidance continues to converge on a solution but significant spread remains among ensemble members. Most solutions show a deepening low pressure system moving in from the northwest. This will bring much cooler and windy conditions, with chances for showers and mountain snow on Sunday. Due to the remaining spread among model solutions, the details of the forecast are still uncertain.
280900z. Coasts/Valleys, Areas of BKN-OVC clouds with variable bases 1800-5000 ft MSL will continue through 16Z Mon, with a gradual transition to SCT-local BKN clouds 2500-4000 ft MSL 16Z-20Z Mon. ISOLD -SHRA will occur through 12Z Mon. Most VIS will be unrestricted below the cloud bases. Only local BKN low clouds are expected to develop Mon evening. Bases will lower to around 1000- 1500 ft MSL for the coastal areas, and 1500-3000 ft MSL inland after 12Z. Any BKN-OVC decks that do form will likely be mostly confined to the immediate coastal areas, and should scatter out completely by 18Z Tue.
Mountains/Deserts, Areas of terrain obscurations will still occur over the coastal slopes and higher peaks due to clouds through 15Z Mon. After 15Z, clear skies and unrestricted VIS will prevail. Areas of west winds with gusts 25-40 kt will continue through 12Z Mon from the mountain crests through the desert slopes and east of passes.
No hazardous marine conditions are expected through Friday, though strong winds, possibly gale-force in the outer waters, could develop Friday night into Saturday.
Elevated surf of 3 to 6 feet with sets to 7 feet will occur through Wednesday. Highest surf will occur on south facing beaches. Strong rip currents are expected. A Beach Hazards Statement is in effect through Wednesday evening for the elevated surf.
Ca, Beach Hazards Statement through Wednesday evening for Orange County Coastal Areas.
PZ, None.
