Thunderstorms and periods of heavy rain throughout the weekend could lead to flash flooding.
A flash flood watch is in effect from Saturday afternoon through Monday morning, according to the National Weather Service in Chicago.
Between 3 inches and 6 inches of rain is expected fall along Interstate 55 as far south as Bloomington and in the areas to the east, including much of northeast Illinois and northwest Indiana, the weather service said.
In the Chicago area, even higher levels of rain are possible with severe thunderstorms. In addition to flooded streets and roads, area rivers and streams are likely to experience flooding that could persist for several days after the rain ends, the weather service said.
A high of 63 and a low of 42 was forecast for Saturday with windy conditions and a chance of showers in the morning. Thunderstorms could move into the area with heavy rain, especially south of Interstate 80 in the afternoon and into the evening.
On Sunday, more showers and thunderstorms were expected with a high of 76 and a low of 49 forecast.