summer thaw
n.β Β«Many schools see a “summer thaw,” when students who have decided in May to go to a certain school change their minds before September, he said. This can create a drop in the number of freshmen actually registering.Β» ββUNH freshman class smallest in three years” in Concord, N.H. AP Sept. 11, 1998. (source: Double-Tongued Dictionary)