The chance of thundershowers Tuesday night in the Tri-Cities has been increased to 50 percent by the National Weather Service.
Scattered showers and thunderstorms are possible mainly before 5 a.m. Wednesday.
Some of the storms could produce small hail and gusty winds.
The weather service has issued a red flag fire warning until 9 a.m. Wednesday.
Critically dry vegetation and lightning increase the potential for numerous new fire starts, the weather service said.