Semantics. Pulling off a +20 like you're talking about would take some obscene daily high and low. right now. We'd be talking record heat levels to pull off. Show me some charts that have hill towns pulling off a 90F high and 65F low in the next couple weeks..
At this point, you can still dethatch, aerate, and topdress the lawn. Lastly, make sure to put a "winterizer" fertilizer down in late October/November. You may want to still to your early fall lawn feeding as well.