Scattered showers and thunderstorms in San Diego County mountains and deserts were expected to continue through Wednesday afternoon, while the heat impacting inland areas will peak Wednesday and Thursday ahead of potentially widespread rain brought on by Tropical Storm Hilary that could drench most of the region early next week.
The National Weather Service issued a flash flood warning for parts of rural East County until 5:45 p.m. Wednesday.
An excessive heat warning will be in effect until 8 p.m. Thursday for San Diego County Deserts, with temperatures of 110 or higher possible, according to the National Weather Service. A less-severe heat advisory will be in effect until 8 p.m. Thursday for the county mountains, where temperatures are predicted in the 90s at elevations below 5,000 feet.
"Widespread moderate heat risk is expected with areas of high heat risk in the deserts," according to the NWS. "Friday through the weekend, cooling will spread well inland with cooler but humid conditions expected through the weekend into next week. Chances of showers and thunderstorms decrease Thursday and Friday with chances falling to 10 percent or less in the mountains."
Early next week, however, is when the weather could get much wetter, thanks to Tropical Storm Hilary. Forecasters said the storm's path is still somewhat in flux, but as it moves north off the coast of Baja California, it will have widespread impacts across Southern California.
"Moisture from this storm is expected to bring widespread heavy rain, along with gusty easterly winds to the area Sunday and Monday," according to the NWS. "This does have the potential to be a very high impact event for portions of Southern California. There is still a degree of uncertainty in the forecast and more details will come on exact timing, location, and magnitude of impacts in the coming days."
