I think it would depend on what kind of turtle you have. Different turtles hatch at different times. I have a painted mudd turtle and she had 9 babies, they are in their shells for 45 days. They will be hatching sometime between the 19-23 of this month.

I live on Cape Cod MA We had a turtle wander into our yard in late May. In the early evening we found her digging a nest at the edge our gravel driveway. We thought after 60 days they would have hatched, to our surprise after some heavy rains, on 9-08-11 in the early evening the hatch began. I reckon it was over 100 days since the eggs were laid.