The National Weather Service in Sullivan has issued a Flash Flood Watch for much of the area, including Waukesha and Milwaukee counties.
Thunderstorms are expected to bring heavy rainfall to portions of southern Wisconsin tonight into early Wednesday. Rainfall of 1-2 inches is expected. If the thunderstorms repeatedly affect the same area, rainfall could easily reach 3-4 inches or even more, according to the weather service.
Areas that received flooding rains early Monday will be more susceptible to additional flooding.
Besides the threat of flash flooding, the rainfall runoff will cause rises on area rivers and streams,k and possibly some river flooding in the next several days, according to the weather service.
The watch is in effect from 10 p.m. Tuesday through midmorning Wednesday.