I drive through Manchester daily, and drive by Stevens Pond, which is right next to/under I-93. In a typical season, that pond is ice free ~3 weeks before ice out on Lake Winni. As of this AM, it still has a decent amount of ice on it, but it is receding, and it looks real thin right on the edge closest to the highway. I would guess that it will be ice free around Monday. Ice out on track for the last week of April IMO.
BTW, my ice out guess is very early May.