Another day of hot and humid weather is expected in Riverside County today, accompanied by a threat of flash flooding in the mountains and deserts because of scattered thunderstorms forecast for this afternoon.
According to the National Weather Service, there is no immediate end to the August heat. Through the week, daytime high temperatures will hover above 100 degrees across the Inland Valley and weather not typically seen in Southern California is forecast.
"Very moist and unstable conditions will produce thunderstorms in the mountains and on desert slopes this afternoon," according to the National Weather Service. "These storms are expected to produce flash flooding in some areas. Portions of the Inland Empire along a line from Lake Elsinore toward Hemet could also be impacted by thunderstorms producing heavy rain."
A flash flood watch is scheduled for the Inland Empire, Riverside County mountain areas and Coachella Valley from 10 a.m. through this evening.
The weather service warned that during that time, excessive runoff from heavy downpours may cause rapid filling and overflowing of normally dry washes, creeks, small streams and low-lying areas. There is also a threat of rock and mud slides below steep terrain in the mountains and recently burned areas, according to the agency.
The Coachella Valley also is subject to an excessive heat warning, which indicates health-threatening conditions resulting from high heat and humidity, until 10 p.m.
"High pressure to the east and monsoonal moisture will continue hot humid weather through this evening," according to the Weather Service. "A weak trough of low pressure over the Eastern Pacific will bring minor cooling and a little less humidity for the middle park of the week."
Daytime highs in the Coachella Valley today are expected to be between 108 and 118 degrees, with overnight lows of 82 to 92 degrees.
On Sunday, a tornado is reported to have touched down along Highway 74 near a Lake Elsinore-area shopping center shortly before 4:30 p.m., according to the Weather Service. There were no immediate reports of damage or injury.
According to the National Weather Service the heat will begin to subside next week, with temperatures dropping to the low to mid 90s by Aug. 20.