How far north would match Chicago’s weather so far this April and be considered normal?

Dear Tom,
How far north would one have to go to reach an area where Chicago’s weather so far this April would be considered normal?
— Bob Lobes, Downers Grove
Dear Bob,
A trip 400-600 miles north would do it. Chicago temperatures through the first half of April have averaged a very chilly 36 degrees, about 10 degrees below normal. The month has already logged 10 sub-40-degree days, and only two days have recorded above-normal temperatures. While it’s been unusually chilly for Chicago, this April’s weather would be typical for upper Midwest locations such as International Falls and Duluth, Minn.; Rhinelander, Wis.; and Sault Ste. Marie, Mich. However, matching Duluth’s weather could be worse. In January 1977, the city’s all-time coldest month averaged 10.1 degrees with 17 days of zero or below — an average temperature for a Duluth January.