February since it's the month with less day xD, anyway August didn't pass that fast but being honest December goes really fast, after X-mas the holidays are almost over
For me August is the largest month, it's winter on that month in my country
I voted for december, you start the month saying : 25 days left for xmas, and then the year finishes and you just realized that xmas has ended . January and Ferbuary , pure summer