Ok, let's go ahead and leave out fall and spring because obviously 50-70 is the most comfortable temperatures.
The battle here is between winter and summer. Let's call winter in MHK the three months of December, January, February and let's call summer in MHK June, July and August. The average winter temperature in MHK is ~32 degrees. The average summer temperature in MHK is ~77.
32 vs. 78. Wow. How is this even an argument? The thing that sucks about winter is that you can't even go outside and enjoy anything. Nobody grills outside during winter. Nobody drives with their windows down during winter. Nobody drinks on patios during winter. There's no winter equivalent to swimming pools (unless you're a bum who stands around a trashcan fire).
You know why? Because being cold is miserable. People grill outside in the summer because, although it's hot, you can stand it. Winter brings snow and ice which makes driving awful and makes everything a mess. Summer brings...some rain sometimes? Some hot temperatures? Big whoop.
Source:
http://www.weather.com/weather/wxclimatology/monthly/USKS0358