Number of 90-Degree Days

Bill’s Blog

Posted: Aug 29, 2020 / 09:50 PM EDT Updated: Aug 29, 2020 / 09:50 PM EDT

We may very well have had our last 90-degree day of 2020. The total number of 90-degrees days for the summer of 2020 stands at 22 for Kalamazoo, 17 for Grand Rapids, 16 for Battle Creek, 15 for both Lansing and for the Muskegon Airport, 11 for Holland and 10 for Jackson. Besides the weather, other factors like location and ground cover determine how hot it can get. There is always some variation (Jackson with 10 ninety-degree days and Muskegon – near Lake Michigan and farther north – with 15 ninety-degree days.

Lake Michigan sunset from Marie Steffen

The number of 90-degree days varies considerably from year-to-year. Note the 32 ninety-degree days in 2012 in Grand Rapids and then none two years later in 2014. We also did not have a 90-degree day in the summer of 1951 in Grand Rapids. Since 1964, the greatest number of 90-degree days in Grand Rapids has been 37 in the very dry summer of 1988. That summer had 14 days that reached 95° and one day that soared to 100°

Grand Rapids reached 100° twelve times in the 1930s, but only 7 times since the 1930s. Our last 100-degree day was July 6, 2012. Muskegon’s highest temperature ever was 99° on 7/30/1913. However, they did reach 97° this year on June 9th (with a south wind that wasn’t coming off Lake Michigan).

Mt. Washington NH is the highest point in the Northeast U.S.

There aren’t many cities in the U.S. that have never reached 100-degrees. Here’s a few with their highest ever temp. in ( ): Marquette MI (99), Sault Ste. Marie MI (98), Barrow AK (now Utqiaġvik) (79), Mt. Washington NH (72), Eureka CA (87), Caribou ME (96), Quillayute WA (99), Hilo HI (94), Flagstaff AZ (97). Miami Beach has only reached 100 once back in 1942.