Here's a link that gives you information on when the leaves are turning and where to see that most color. The leaves where I am (lakes region) seem to be turning earlier than usual, so you should see some vivid colors. The Cog Railroad is fun (a bit pricey) and there's also a van that takes people up Mount Washington, too.

Here's a link that gives information on when leaves are turning in the different regions of the state.

https://www.visitnh.gov/seasonal-trips/fall/peak-foliage-map