Areas of cumulus clouds along and west of the coastal mountain slopes this afternoon will clear overnight. A drying pattern will develop for Sunday through Tuesday, with periods of weak to moderate strength gusty Santa Ana winds. Slight warming will accompany the offshore flow for Monday and Tuesday. A low pressure system from the southwest could bring a return of precipitation for Wednesday through next Saturday.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
This afternoon, Areas of low clouds formed along the coastal mtn slopes, and in the coastal areas and valleys. The clouds will likely clear tonight so temperatures could fall into the 30s in parts of the inland valleys early Sunday morning
Dry and warmer conditions are expected for Sunday through Tuesday as high pressure builds over the west coast and a positively- tilted trough extends to the southwest over SoCal with a closed upper low forming to our southwest. Offshore flow develops on Sunday and persists through Tuesday as a sfc high moves into the Great Basin. The offshore flow gets some upper level support on Mon and Tue with northeast winds aloft. The offshore flow will likely be strongest on Tuesday, producing gusty Santa Ana winds in the mtns and lower elevations west of the mtns. Northeast to east winds gusting 35-45 mph will be possible in the favored locations. Tuesday will also be the warmest day, with high temps in the 70s west of the mtns and most areas seeing temps near or above seasonal averages. Coastal and valley areas could be as much as 7 degrees above average while the mtns and deserts will be near or just a few degrees above.
Chances for rain and mountain snow will return for Wed through next Sat as a low pressure system moves in from the Gulf of Alaska, causing the closed low to our southwest to become an open wave as it is drawn into the mean westerly flow over the Southwest US. Forecast details are still uncertain due to differences in model solutions but it's likely that we will see periods of showers between Wed and next Sat. The timing is also in question but preliminary estimates are for totals of 1"-1.5" in the coastal areas and valleys, 1"-3" in the mtns, 0.3"-0.6" in the high deserts and 0.15"-0.30" in the low deserts. The snow level will remain above 8,000 ft through Friday before lowering to around 6,500 ft on Sat.
271630z, VFR condition are expected through the TAF period with some lingering 3000-5000ft MSL clouds across San Diego County into tonight. Offshore winds will pick up after 15z Sunday, with gusts up to 25-30kts for the coastal slopes of the mountains and into the valleys. Higher gusts through mountain passes with mod up/downdrafts near mountain peaks. Strong winds prevail into Monday.
No hazardous marine weather expected through Friday.
High Surf conditions are subsiding and will continue to do so. Therefore, the High Surf Advisory has been cancelled.
Ca, None. PZ, None.
