Vernal Equinox 2024 Date And Time. But why does the day mark the start of spring and why only in the northern hemisphere?. For the model e ar5 simulations, all years have exactly 365 days and vernal equinox always occurs on march 21, hour 0.

The vernal equinox will occur at 3:06 a.m. In different time zones, the date of the equinox may differ by a day, so it is important to indicate your exact location.