RI in late September
 

My husband will be in Warwick, RI September 21-25 for a meeting. We plan to spend an additional 5 days in RI and/or Massachusetts. Should the five days be before Sept. 21 or after Sept. 25? Is late September a good time for fall foliage, or is that too early? Also, what recommendations do you have for things to do, places to stay,etc. We are also thinking about going to Martha's Vineyard and the Cape Cod area. Any comments on this would be appreciated.
RHunt

September is a great time to get away. The weather is still warm enough to enjoy outdoor activities.I would go after your conference. You might get some good tips from other people. It will be too early for any peak foliage but some of the trees should be turning but not necessarily in RI or the Cape.
Cape Cod will be pretty dead that time of year. I'm not a big M.V.fan but I do like Provincetown at the end of the Cape. Things should be winding down there and many of the stores will be closing for the season.
A visit to Newport would be great and maybe a couple of days over to Block Island.

You should definitely plan to spend a day or half a day in Newport, a few hours at Watch Hill (in Westerly) and of course some time in Providence. It is too early for foliage, but still a great time to visit.

Choose the 5 days after so you might see the start of some foliage. Providence has some great restaurants. You can get recommendations with a search on Providence. Hotels in Providence are expensive so you might want to continue to use Warwick as a base. It would be a great time to explore Cape Cod. Check on availability of places to stay on Martha's Vineyard. We heard that Sept was a popular time for weddings there and lodging was booked up early. You might check to see if Providence is having Waterfire during your visit. That's when bonfires are lit in the canal, music, etc. Newport would make a great visit.

Late September is ideal weather in New England (except, on the slim chance that a hurricane is coming up the coast).

Dry, warm days, cool nights...The leaves are starting to turn...

Depending on your tastes, you might want to check out the harvest festivals that occur this time of year in most every town.

On average in Mass. the second week of Oct. is peak foliage. You would probably need to go a bit north to see much in the 3rd or 4th week of Sept.. The Green Mountains of Vermont or the White Mountains of NH are very popular at that time (both are about a 3 hour ride from RI). If you wanted to stay closer, I'd also say Newport, Block Island, Martha's Vineyard, Nantucket. My suggestion is to book early though! Best of luck and have fun!