Dry conditions expected through Wednesday afternoon. For Wednesday evening into Thursday, there is a slight chance of showers with highest chances in the mountains. Temperatures will remain near to below average through Thursday. Then dry and warmer for the weekend followed by cooling for early next week.
For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,
Dry conditions expected through much of Wednesday. High temperatures through Thursday are expected to run near to slightly below average, with conditions warming each day. The biggest jump in high temperatures will be between today and Tuesday, with Tuesday 7 to 15 degrees warmer than today for inland locations.
A low pressure system well off the coast of northern Baja on Tuesday will move slowly eastward and inland over northern Baja or far southern California Thursday. Chances of precipitation are in the forecast as early as Wednesday evening and continue into Thursday. Highest chances of precipitation are in the mountains (15 to 20 percent), with 10 to 15 percent chance elsewhere. There remains uncertainty in the track of this system which has significant impact on precipitation chances across the area. A more northerly track along the border of US/Mexico will increase precipitation across the area, including the deserts and desert slopes of the mountains. A track further south into Baja may keep conditions dry. Right now the ensemble guidance is split 50/50 with 50 percent of solutions showing a track that would bring precipitation including wrap around precipitation to the deserts and 50 percent are showing no precipitation for Thursday. Nbm chances of rainfall totals exceedng 0.10 inches between Wednesday evening and Thursday evening are 10 to 15 percent for the coast, valleys, and San Diego deserts and locally up to 20 percent for the mountains.
About 60 percent of ensemble solutions indicate dry conditions will return on Friday, with about 40 percent showing the potential for lingering precipitation. There is much higher confidence in dry weather returning for Saturday with a warming trend expected. High temperatures on Saturday will be 5 to 10 degrees above average for inland areas, ranging from around 70 near the coast to the 80s for the Inland Empire with the lower deserts in the mid to upper 90s.
Another low pressure system will approach the US West Coast Sunday or Monday, brining cooler conditions and likely an increase in winds for the mountains and deserts. Some ensemble solutions are indicating the potential for another round of precipitation, but there remains uncertainty surrounding how far south the low will track. A more southerly track increases our precipitation chances while a more northerly track decreases them.
280400z. Coast/Valleys, SCT-BKN clouds 3000-5000ft MSL develop mainly over San Diego County after 06z, scattering out around 12z with FEW-BKN high clouds AOA 20,000ft MSL thereafter. Very patchy low clouds with slightly lower bases than tonight may develop again over coastal SD Co. later Tuesday night after 06z.
.Mountains/Deserts, Westerly winds are slowly weakening tonight, only gusting above 35 kts in the Banning Pass. Mod to strong up/downdrafts near peaks and on desert slopes. Gusts increase again Tuesday afternoon, around 30 kts in the desert slopes (~35 kts through the Banning Pass) after 01z Wed.
West/northwest winds expected to gust near 20 kts in the outer waters Tuesday afternoon and evening. No hazardous marine conditions are expected through Friday.
Ca, None. PZ, None.
