Spring starts at different times depending on the definition used:
- Astronomical spring begins on the vernal equinox, which usually occurs on March 19, 20, or 21 in the Northern Hemisphere. In 2025, it will begin on March 20. This marks the moment when day and night are approximately equal in length and daylight starts to increase.
- Meteorological spring starts on March 1 and lasts through May 31. This method divides the year into four fixed three-month periods for easier weather and climate observation.
Thus, spring typically starts either on March 1 (meteorological) or around March 20 (astronomical) in the Northern Hemisphere.
