Where I live, the weather is pretty moderate. We occassionally have very hot days but they are few and far between. Because of the temperate weather, I really don't have "summer knitting" versus "winter knitting" -- although I will not do a huge blanket in the middle of summer.
Yesterday was one of those few & far between days. The high was supposed to be 107 deg F. And it was never going to get any cooler than 75.
I picked up my Ribby Cardi that I had been working on, and managed to get through two rows, before setting it back down in disgust because...It Was Too Damn Hot To Knit.
Then when the evening rolled around, I simply sat & spun, while watching movies. This was much easier in the heat, then trying to knit anything.