Answer: It might be that the grass will recover if you water regularly. If you think it's too far gone for that, you may want to overseed now and keep it watered throughout the fall and winter months. If it's a very old lawn, renting an aerator will improve compaction. Once aerated, overseed and water well. Whichever tactic you employ, you should see results in a few weeks.
Best wishes with your lawn!
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