1st Day Of Spring 2024. The spring equinox (march 19, 2024) signals the start of spring in the northern hemisphere, the beginning of autumn in the southern hemisphere, and a rare moment of equal night across. The first day of winter is marked by the winter solstice, which occurs when the earth’s axis tilts farthest.
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. The vernal equinox arrives on tuesday, marking the start of the spring season for the northern hemisphere.