When Is Spring 2024 Uk. An equinox is one of two days in the year when the sun crosses the equator and day and night become equal in length. Monday 14 to monday 21 october 2024;
The first day of spring in the uk astronomically occurs on the vernal equinox, 20 march 2025. The spring equinox begins on march 20, which is the first day of astronomical spring.