Is this a good time to dethatch?

[tonym]

I live in NE PA. Is this a good time of year to dethatch, or is spring better?
I can rent a dethatcher attachment for my Walker from my Walker dealer for $25 , I think my lawn can use it, it has been dry summer, lots of brown areas. Is this a good thing to do?

[Az Gardener]

The best time to dethatch is when the turf is actively growing. All that thatch is storing sugars and starches that will be needed in the spring when the turf come out of dormancy. If you remove it now it will have less stored energy and take longer to rebound in the spring ultimately making for a weaker turf. I deal with only warm season grasses but grass is grass, I cant think of a good reason to dethatch now but someone else may. Lets see, survey says?