I'm in Southern
New England.
The weather around here is unpredictable in any season.
Last week it was in the 50's and raining. But won't get above freezing all of this week, and snow is expected tomorrow.
For
boating, September can be very nice. A little cooler than July and August, more 60's and 70's than 80's. Less
fog. Some 50's at night. A little breezier than mid summer.
These are just generalizations. Last summer it rained at least one day every weekend for 7 or 8 straight weeks in September and October. And while we don't get many direct
hurricane hits, we do get "remnants" pretty frequently.
Actually, it is usually pretty nice overall that time of year, you just can't count on getting a nice warm week (if you are thinking of chartering).