Even with the recent low temperatures in New Hampshire, ‘‘ice-in’’ at Lake Winnipesaukee is a little behind schedule. Emerson Aviation, which has the task of deciding when the entire lake freezes over for the first time during the winter, made the determination on a Tuesday morning flight. Conditions were helped by freezing temperatures over the past week. However, some melting was expected Wednesday, due to higher-than-normal temperatures. Dave Emerson of Emerson Aviation told The Citizen in Laconia that Tuesday’s declaration was a few days behind schedule.