More than 4 million people across five states were under winter storm alerts on Sunday as heavy lake-effect snow continued to bury the Great Lakes region, prompting emergency declarations and the deployment of National Guard troops to rescue stranded motorists.

In Erie County, Ohio, a lake-effect snow warning is in place until 7 p.m. on Tuesday. Between 10 and 20 inches of heavy snow accumulations are expected in the north of the county, while between 12 and 24 inches are expected in the south.