BENTON, Ill. — Up a quarter-inch of ice is forecast to coat roadways in central and southern Illinois this weekend.

The National Weather Service has issued ice storm warnings and freezing rain advisories for parts of central and southern Illinois, including Quincy, Springfield, Effingham and Carbondale. The weather service says that higher amounts of ice accumulation are possible along and south of Interstate 72 through Sunday.

The state of Illinois on Friday afternoon closed four historic sites “out of an abundance of caution as an ice storm approaches.” They include Cahokia Mounds in Collinsville, Fort de Chartres near Prairie du Rocher, Lewis and Clark in Hartford and the Vandalia Statehouse.

Downed trees were reported in the Carbondale area and the Illinois Department of Transportation reported roadways covered with patches of ice and snow in southwestern Illinois.