It's been a strange winter for ice on Canobie Lake. Sheltered coves began to freeze in early January, but other parts froze later and the main part of the lake still has open water. So the ice thickness is not uniform. It may be thick enough to support you near the shore, but not a little farther out.
Last weekend (January 30 & 31) the air temperature went up into the fifties, and there was considerable ice melting. The usual advice is that 4 inches of ice is thick enough to support individuals, but that's for clear ice. Ice that has melted and refrozen may be weaker than that. Be careful. Err on the side of safety.