Several inches of rain dropped on parts of Northwest Indiana, where some roads were nearly impassable at the height of the storms overnight and standing water was still visible early Tuesday morning.

The Metropolitan Water Reclamation District issued an “Overflow Action Day," urging residents and businesses to take steps to help reduce flooding and protect water quality.

The severe thunderstorm watch means residents should be prepared for dangerous weather conditions.

By reducing water during these storms, area residents and businesses can help reduce flooding and protect water quality.

Every year, the International Monarch Monitoring Blitz invites residents across the continent to participate in protecting this iconic species.

Before severe storms, the MWRD lowers the level of the Chicago Area Waterway System as staff work around the clock managing the excess water.