You may notice that the first day of spring isn't always March 20th. Sometimes it's the 19th or the 21st. This happens for two reasons:
To make record-keeping consistent, meteorologists divide the year into four seasons of exactly three months each, based on the annual temperature cycle. when do the 4 seasons start
If you ask a meteorologist (a weather scientist), they will likely tell you that seasons start on a completely different schedule. You may notice that the first day of