The first day of spring
Arnold Trachtenberg (Mon, 20 Feb 2006 14:00:26 PST)

Jim:

Found a definition;;

Meteorological spring: Comprised of March, April and May, it begins on
March 1. Astronomical spring extends from the vernal equinox to the
summer solstice (about March 20 to June 21).

So I guess senility starts early too.

Arnold