High pressure over the Southwest was predicted to bring increasing monsoonal moisture to Southern California this weekend, the National Weather Service said.
Thunderstorms were possible, mainly in the mountains and deserts Saturday and Sunday afternoon and evening, the NWS said. Showers may drift across the coastal and valley areas Saturday night into Sunday morning.
Marine layer clouds may be more limited due to the monsoonal flow and higher sea surface temperatures. This pattern was expected to also favor higher humidity and warmer nights.
Saturday’s highs were expected to be 104-109 degrees in the deserts, 88 to 95 in the mountains, 87 to 92 near the foothills, 71 to 76 along the coast and 76 to 81 farther inland.
💧 Isolated tstorms in the mountains this afternoon
💧 Few showers anywhere tonight; a tstorm is possible
💧 Better chance of tstorms mountains/deserts on Sunday with localized flash flooding possible.#Monsoon #CAwx pic.twitter.com/2VoHWteqLP
— NWS San Diego (@NWSSanDiego) July 17, 2021
The best chances for thunderstorms look to be Sunday afternoon, the NWS said.
Periods of isolated to scattered showers and thunderstorms may be seen much of the coming week as a weak monsoonal flow continues.
High temperatures were predicted to be near seasonal summer norms next week, but nights may be a little warmer than normal.
Night and morning low clouds at the coast were predicted to be more patchy and intermittent.