A flash-flood watch was issued in the Inland Empire Tuesday due to expectations that a thunderstorm would bring "very heavy rain" to parts of the region, according to the National Weather Service.
There are chances for rain and thunderstorms in the mountain and desert areas of Riverside and San Bernardino County.
Areas east of Interstate 15 are covered by the flash-flood watch, which means those along the banks of washes and creeks should move to higher ground, the weather service said. A flood watch began 11 a.m. Tuesday and is set to last though the evening.
A more severe advisory, a flash-flood warning, has been issued for south central San Bernardino County along Amboy Road near Sheep Hole Pass, the weather service said. That warning was set to remain in effect till noon Tuesday.
Heavy runoff from the expected downpour is a threat, as are mudslides and rock slides in recently burned areas, the weather service said.
Meanwhile, triple-digit temperatures are expected to linger in the low and high deserts through the weekend.
In the mountains, the chances for thunderstorms should decrease by 20 percent Wednesday with temperatures in the upper 70s through the weekend.