I second the suggestion for the Anthony Bailey book to get a feel for the area.Do you mean the Eastern end of CT? If so, then it simply doesn't get any better than that. I believe that the Eastern end of CT one of the top areas of the US for cruising sailing adventures. Much better than the Western end of CT. We lived and sailed out of Mystic CT for 18yrs. You can daysail all the way up to Cape Cod, Martha's Vineyard, Nantucket, and Buzzards Bay. Newport, Block Island, the Eastern Forks of Long Island (Montauk, Hamptons, Sag Harbor, Shelter Island, etc) and more are only an afternoon's sail away. Fisher Island Sound is protected water in almost all weather, so if it is not great weather for adventuring farther, you can still sail out to Fisher Island, Stonington, Essex, New London, and other places along the coast. Lots and lots of small towns to anchor off and explore by foot, as well as wilderness areas to do the same. If you feel like sailing West, there is this town called "New York" that I've heard has a few things to see in it.
If you have a house and sailboat for the summer anywhere near the Mystic area of CT, it will be the best summer ever. I had 18 of those summers and still miss them. We left and have explored the Chesapeake many times, as well as the Bahamas and the entire Caribbean Sea. There is nothing like summer sailing in New England.
As far as the sailing itself goes, the predominant winds are SW, and they get light during the summer there. When they are light, you can count on a seabreeze picking up in the late afternoon into early evening. This is a magical time for a couple hours sail. The water stays cooler until late summer, so the air on the water is also cooler. Don't be fooled by high inland temps - it will be much cooler on the water. You will need a sweatshirt at night. Humidity is high, so the afternoons with light winds can feel warm, but that doesn't last long. When a cold front comes through, the winds switch to the North which is offshore there, the humidity goes away, and sailing along the CT coast doesn't get any better - good winds and flat seas with crystal blue skies while you beam reach along the coast, then beam reach back home.
The season is short, though. But it will be the best there is.
Do yourself a favor and pick up this book: The Coast of Summer: Sailing New England Waters from Shelter Island to Cape Cod by Anthony Bailey (1995-08-01): Amazon.com: Books
Interesting observation... YES there seems to more fog east of Montauk. I have seen some dense fog in Block Island & Rhode Island Sound... West Harbor , FI, Stonnington and the waters north of the Race. While I have seen for further west it is not as dense, as often or as widespread. I suspect it is because the fog is coming off the ocean and the air is not warmed by Long Island.One thing to be aware of in the Eastern end of LIS and areas like Stonington, Newport and areas east is occasional Fog. I was anchored in Watch Hill one time and saw the most dense fog I had ever seen. It becomes less prevalent the further west one sails. It usually clears eventually but, if you are not use to it it can be unnerving if you are underway. Though it is awesome to see if you are safe at anchor.