I live in Texas and temps are unseasonably warm now, so it may be that we are heading into a hotter summer than usual. Remember that it can take up to 2 weeks for your body to acclimate to running in the heat and even then, your pace is going to be much slower than it would be when you are running in more typical temps (50 and 60 degrees). Make sure you stay hydrated, but don't push fluids...you do not want to over-hydrate, which can be more dangerous than be dehydrated.
If you can find a shady area to run, that may help too. And of course finding a friend to run with may help you run earlier in the morning.