Spring arrives on March 20. But did you know that March 1 is really the first day of spring? Astronomical Spring starts March 20, but Meteorological Spring begins on March 1. So what’s the difference?
Astronomical Spring is the day most associate as the first day of spring. It marks the day the vernal equinox occurs, when the sun shines directly above the equator making day and night both 12 hours long (on average for most mid-latitude locations). Meteorological Spring is when the meteorological community mark the changes in temperatures and precipitation in the mid-latitudes. Winters (December, January, and February) are usually the months with the coldest temperatures and the largest amounts of either snow or precipitation depending on location. Summers (June, July, August) are usually the months with the hottest temperatures and are either the driest or rainiest, again, depending on location. So the months in between the extremes are spring and fall. It doesn’t mean things are going to be automatically warm or going to rain but in meteorological terms, spring begins March 1.
Oh happy day, regardless of which day it starts!
Source: Mount Washington Observatory