Grand Rapids, Michigan, Climate Update for September 2018
Max temp 90, Mean Max temp 89
Min temp 40, Mean Min temp 37
Av temp 66.1, Mean Av temp 62.7
Precip 5.93, Mean precip 3.57 (quack quack, another gullywasher)
Cooling Degree Days 135, Mean CDD 76, Season to date 983, Mean Season to date 690
The cooling season to date as measured by CDD is now 42% warmer than the mean to date. Season to date 2018 is now 7th warmest on record for total CDD. The warmest year on record was 1921 with 1200 CDD. The 2nd warmest year on record was 1931 with 1061 CDD. It is highly unlikely that 2018 will finish warm enough to crack the number two spot but will be firmly in the top ten warmest years by CDD. There have been five months in a row in 2018 with max temps in the 90s, the first time that has happened since 1991.
