Iowa here. I'd kill to have 30 F temps in the winter. In December and January, the usual high during the day will be in single digits or low teens, and a lot of days are well below 0 F, both during the day and at night. We usually have 4-6 days a year that get down to like -25 F with a windchill at like -40.
Minnesota is in general a little colder than Iowa, but not by much. Canada is colder still, but Iowa is far from a warm state. 40-60? Lol.