A combination of rain and runoff from melting snow has prompted the National Weather Service to announce a flood watch for the Des Plaines River at Riverside. The National Weather Service is predicting that the river will rise to 7.6 feet by Monday night, inundating low-lying areas in the forest preserves and wooded areas bordering the river. Swan Pond Park could also be affected. Flood stage is 7 feet. The National Weather Service predicts the river will hit flood stage by mid-morning on Monday.
As of 10:45 a.m. Sunday morning, the river had risen to 4.29 feet. That was a jump in water level of more than a foot since midnight, and the National Weather Service expects the river to continue to rise as rain helps melt snow north of the Chicago area.
The weather service stated the runoff could be greater than normal because of frozen ground beneath the snow. North of Chicago, the ground is frozen to up to 10 inches, which will prevent the water from the melting snow from being absorbed.