Many universities, including my own, begin today. And it is currently 65 degrees (F) and sunny here in Pittsburgh.
Let's hear from the Reverend Professor Simon Darcourt:
"Autumn, to me the most congenial of seasons: the University, to me the most congenial of lives. In all my years as a student and later a university teacher I have observed that university terms tend to begin on a fine day."
(Robertson Davies, The Rebel Angels, 1981).