Can we blame climate change for heat waves?

Generally not, according to Joshua Keating:

While the planet is undoubtedly getting warmer, attributing a particular weather phenomenon to this shift is a bit problematic. Although the science may be on the side of climate change, blaming one particular weather incident on global warming is just as misleading as saying that a cold winter disproves it. "I don't think anybody in the climate change community had even heard the word 'derecho' before last week," says Gavin Schmidt, a climate modeler at NASA's Goddard Institute for Space Studies.

"If you really want the nation to be aware of climate change, severe weather outbreaks are certainly a way to get people's attention. But to attribute a specific one to climate change is, at this stage of the game, impossible," says Otis Brown of NOAA's National Climatic Data Center. According to Brown, by 2100 Chicago is projected to have the kind of temperatures we now associate with Dallas, but the change will be gradual and far more difficult for the public to comprehend than a two-week spell of 100-degree days that may or may not have anything to do with global warming.