Today will be the coolest day of the week, with temperatures 10-25 degrees above average Monday through at least Saturday as high pressure builds back into the area. Areas of low clouds and fog will spread into the coastal areas each night and morning early this week.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
A transient short wave trough moving through the region has resulted in cooler (relative) temperatures, and today's temperatures are 1-10 degrees lower than yesterday's at the same time. The trough will also bring low level marine layer clouds, currently offshore, into coastal regions and western valleys this evening a little earlier than yesterday. The marine layer will be low enough tonight to result in more fog for higher elevation coastal regions, generally for areas approximately along the I-15 corridor in San Diego County and the I-5 corridor in Orange County; similar areas to this morning. Marine layer clouds will return to coastal areas each evening/morning through at least mid-week, moving inland to a fairly similar extent each night.
Our little weak low moves off to the south early Monday, and broad ridging will settle back over the area through mid-week, resulting in another warm-up. Temperatures tick up slightly each day through Wednesday, remaining a warm 15-25 degrees above daily averages through the rest of the week, with little day to day change in temperatures through Saturday. While temperatures this week won't rival monthly records, as in the last week, multiple daily temperature records (both high and morning lows) are likely to be broken throughout inland Southern California most if not all days through Saturday under anomalously strong, early-season high pressure.
A broad trough will move over the western U.S. Late this week into next. Though differences in ensemble position/strength/timing of the trough remain, this will result in cooling Sunday likely continuing into next week.
230000z, Low clouds are developing off the coast, expected to move onshore 03-05z with widespread ceilings around 300-800 ft MSL throughout the coast. Clouds fill in inland - up to the valleys around the I-15 corridor in SD Co. and throughout inland OC - between 06-08z. Expect vis restrictions for elevated coastal terrain and inland valleys of 1-4SM (with localized FG, 0-1SM vis) and coastal sites 4-6SM. Scatter out 16-18z Mon. Everywhere else, VFR conditions through the TAF period.
Low clouds are developing over the waters this evening. Areas of mist and patchy fog are expected under the main cloud deck, although sparse in coverage. Greater confidence in higher fog coverage Monday night and Tuesday night. Otherwise, no hazardous marine conditions expected through Friday.
Ca, None. PZ, None.
