Historically Summer has never been my favorite month. The heat doesn't bother me too much, but certainly I prefer 50 degrees to 90 degrees. In the cold you can always put on more clothes and stay warm, but if it gets too hot out there just isn't much you can do to avoid the heat if you want to be outside.
Since moving to Alaska 6 years ago though my perspective on Summer has changed a lot. In Juneau it rarely gets over 75 degrees. Beginning sometime in April and continuing until sometime in September the high temperature is between 50 and 75 almost every single day. Perfect temperature as far as I'm concerned. Sure it rains a lot, and sure the winter's can be pretty dark and miserable, but there are few places I have ever been where the temperature is as ideal for 6 straight months as it is in Juneau from April to September.
It's a little over 80 in Boulder today and I can't help but feel like I'm getting out of here just in time before the real heat sets in. Sure, it's only supposed to be about 50 and raining when I touch down in Juneau on Monday, but for running 20+ hours of rugged mountain terrain each week I'd take 50 over 80 in a heartbeat. The rain might take a little while to get reacquainted with (it's rained maybe 3 times in the 8+ months that we've been in Colorado), but even the rain this time of year in Juneau has a way of feeling gentle and comforting.