Are people at northeast liberal arts colleges happy?

Northeastern locations vary in temperature, of course. Of the schools you mentioned, the winters at Williams wouldn’t be quite as cold as at the other three colleges, for example:

Average January Low (F)

Williams: 12.1°
Bowdoin: 9.0
Middlebury: 8.8
Colby: 8.1

(Data from Sperling’s.)