Dry and warmer through the end of the week, with high temperatures rising to as much as 10 to 20 degrees above seasonal averages. High clouds and weak offshore flow will continue through Tuesday, then weak onshore flow returns with increasing chances for a return of marine layer low clouds later in the week.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
Tonight through tomorrow night,
High pressure conditions continue to build in over the region. There has been enough weak offshore winds to prevent any marine layer development. Some of the higher valleys may experience patchy fog this morning, otherwise with the exception of some passing high level clouds, skies will remain mostly clear and temperatures this afternoon will be slightly warmer from where the highs were yesterday. Beginning tomorrow evening/night, we could have some of the marine layer beginning to develop just over the coastal waters, and then possibly move in over some of the coastal areas.
Wednesday through Saturday,
From Wednesday through Friday, there will be a warming trend as the ridge over the western states continues to strengthen. A more persistent onshore flow will also allow for a return of the marine layer. Winds will increase on Wednesday with a tightening of the gradient as a trough passes to the north. With a 1000/500 mb thickness of 590 dm parked just to the south of San Diego by Friday, temperatures are going to be well above the seasonal temperature for this time of year, where some areas within the IE may approach 90 degrees and be nearly 20 degrees above average. High temperatures for Saturday will be slightly cooler as the strong ridge finally begins to weaken.
A little beyond the forecast, there looks to begin a change in the longwave pattern shifting from being predominately by a ridge over the western states, to transitioning into weak troughing over SoCal. This will allow for a breakdown and continued gradual cooling through the following weekend. This may lead to general weak troughing remaining in place after that going into the week beyond that, and this will begin to cool off temperatures closer to the seasonal average, and also allow for a slight chance of precipitation, as ensembles suggest.
231030z, VFR SCT high clouds today and tonight.
No marine hazards are expected through Friday.
Ca, None. PZ, None.
