Chicagoans were warned of severe showers and thunderstorms Wednesday and chillier days immediately after — including the possibility of frost Thursday and Friday night.

An isolated storm warning was issued for the city Wednesday, as showers sweep across northern and central Illinois as well as northwest Indiana, according to the National Weather Service. Temperatures will range from 73 to 77 degrees.

In Chicago, weather will dip to between the high 40s and low 50s the rest of the week, however, the NWS said. That could mean frost emerging Friday and Saturday morning. Rain was expected Friday and Sunday.