Various individuals congregating at park after dark and many loud individuals during 11pm-2am on Thursday, Friday and Saturday nights
I would also suggest having your neighbors call the same complaint in around the same time and doing so whenever this is an issue. My guess is one-off complaints don't get much attention; squeaky wheel is the way to go!
School is back in session. This seems to vamp up as soon as the students are back to partying at the Wintergreen Apts. Inadequate parking in the apartment lot forces the quiet street to fill up with cars until they return at 12-2am and make a ruckus.
They don't want to seem to do anything with this car that seems to have been parked on the street since June. I'll place my own complaint.
Problem has escalated to honking horns, loud yelling and people in the middle of the street.
Try talking to Wintergreen Management and ask if they would send a notice or flyer out to their residents asking them to request that guests parking on Stone Street be respectful of the neighbors there, especially late at night. If it's approached in a "we would like your help managing this, what do you think" way, rather than confrontational, I think more likely to get some assistance. The management office number is 203-389-7593.
And also call the NHPD when it's happening! Non-emergency number as posted below or 911 if/when it's out of control or an emergency.