March 20 - June 20
Spring Starts: Saturday, Mar 20 2:37 am PDT
Spring Ends: Sunday, Jun 20 8:32 pm PDT
The first day of spring (March equinox or vernal equinox) is when the sun shines directly on the celestial equator passing from south to north and the length of day and night are almost the same. This is referred to as astronomical spring or the March equinox or vernal equinox.