Hot and sweaty. Smelly crowds, short tempers. We don't do summer in theme parks. Florida hot is not like any other hot.
I agree with the "hot and sweaty" part, but we actually like going in the summer.
Longer hours, more attractions open, daily parades and fireworks.
As for our strategies, we get up early and do the AM EMH. Then when the heat builds by about 11 am, we head back to our resort and cool off and nap. We stay there until the afternoon showers are over, and head back out to the parks around 4 to 5 and stay late.
Works great for us!
Oh, and in answer to your question, it was mid 90's last week (92 - 96), with heat indices in the 104 - 106 range, with 20 to 40 % chance of scattered afternoon showers every day.
And the crowds were not bad! DH and I commented that it seemed a lot less crowded than around the same time in the past. I think it is a combination of the economy, the heat, and WWOHP siphoning off some business. For example, we only had to get a few Fastpasses (for things like Toy Story Mania, Soaring, Test Track, Space Mountain). Everything else was a reasonable wait.