A warning sign is covered by ice at Clark Square park in Evanston, Ill., Wednesday, Jan. 30, 2019. A deadly arctic deep freeze enveloped the Midwest with record-breaking temperatures on Wednesday, triggering widespread closures of schools and businesses, and prompting the U.S. Postal Service to take the rare step of suspending mail delivery to a wide swath of the region. (AP Photo/Nam Y. Huh)
