Spring Equinox 2025. When is the first day of spring in 2025? 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 are almost the same.
Friday, jun 20 10:32 pm edt. The spring equinox 2025 is a significant astronomical event that marks the beginning of spring in the northern hemisphere and autumn in the southern hemisphere.