What Is Spring Equinox 2024. We greet the first day of the new season with the spring equinox, but what is it, exactly? But what exactly is the spring equinox, and why does it start this year at precisely 4:06 a.m.?

This year, the spring equinox falls on wednesday 20 march, and the astronomical spring lasts until the summer solstice. Spring will last from march 19 until june 20, when summer officially starts in 2024.