Spring Equinox 2024 Season Dates. An equinox is one of two days in the year when the sun crosses the equator and day and night become equal in length. At spring equinox, astronomically speaking, we can wave goodbye to winter and welcome spring, summer, and sunny weather.

In the northern hemisphere, the astronomical start of spring is also known as the spring equinox. Astronomical spring, discussed here, relies on earth’s position in its orbit, commencing with the vernal equinox.