The change in annual average summer temperatures from 1970-2024 was calculated using linear regression. Climate Central's local analyses include 247 U.S. weather stations.

The PHZM is based on "the average annual extreme minimum winter temperature." The 2012 map used historical data of the average annual minimum temperature from 1976 through 2005. The 2023 map uses ...

According to the National Weather Service, in 2024 the average annual temperature was 44.1°. This broke the record of 43.8° in 2012. Marquette WLUC.