This is the place to be in the summer if you like comfortable temperatures. The maximum average high temperature at the National Weather Service near Negaunee is only 76° from early July through early August. That means a high of 80° is a warmer than average summer day.
Continuous weather records have been kept at the site since October 1961. During these 61 years, the earliest 80° high was on March 21, 2012. The latest occurred on October 17, 1961. That means only four months– November, December, January, and February– have not reached that warm summer benchmark.
The most 80° highs in one year was 56 days in 2007. Second place was fives years earlier in 2002 with a total of 49 days. The least was only 17 in the chilly summer of 1967. There were 18 days of 80° or warmer in four years: 1962, 2000, 2009, 2014. The long-term average is 31 days per year.
On the other hand, 90° days cross the threshold of “warm” into the “hot” territory. These hot days are a relatively rare phenomenon in Upper Michigan. The average number of 90° days at the NWS is only three per summer.
The most was 13 days in the long, hot summer of 1988. Last year, there were four days of 90° or above. However, over the past 10 years, hot weather has been at a premium in the U.P. The most recent 10-year average is 1.4 days per summer at 90° or warmer. So far in 2023, we are already about the recent 10-year average of 90° days.