When Does Spring Start, Really?

Spring, as a season, is defined in the Merriam-Webster Dictionary as "the season between winter and summer comprising in the northern hemisphere usually the months of March, April, and May or as reckoned astronomically extending from the March equinox to the June solstice". While the astronomical definition is easy enough, it doesn't seem to match meteorological spring, or at least it seems too broad a range of dates, considering how early and mid-June might be astronomically "spring" but is often as hot as the summer months of July and August. On the other hand, including early and mid-March within spring, if you define March, April, and May as the spring months, is a good joke. Where I've lived, winter weather persists through all of March and parts of April. Sure, there might be some thaws that happen in March, and maybe even some sprouting grass, but overall March is more like the last winter month to me. Many times, my "spring break" was in March when the trees were still bare, and the ground still had snow. Then, there are times when snowstorms, sometimes of great intensity, happen in March and especially April as winter has its last fun. "I cried for spring to come, but here, winter remain", as the lyric goes in Sabaton's "Soldier of Heaven".

Picture from Easter 2020: a basket of Easter eggs contrasts with snowfall outside.

What does define spring, in that case, apart from the time between the March equinox and the June solstice? I think we have to exclude snow from that definition, if our association of snow with winter is valid. In that case, spring should not have freezing temperatures at all. On the other hand, the hottest temperatures should be reserved for summer. There is, however, a broad range of temperatures between feeling hot and feeling cold enough to get frostbite. I choose this medium to define spring temperatures. At this point, the upper limit will vary from person to person. For me, I'd set it at 25 degrees Celsius, or 77 degrees Fahrenheit. There was only one Easter I can think of that actually felt slightly summer-like, and that was when the high temperature was at the temperature I just mentioned.

Therefore, I would say that spring in the Northern Hemisphere is all the days between January 1st and June 30th when the temperatures all day are from 0 to 25 degrees Celsius, or 32 to 77 degrees Fahrenheit. This covers any early warm days and any late cool days but excludes freezing cold days and hot days. For your amusement, I have a picture from possibly the earliest first day of spring by my definition: February 1st, 2020, when I was at South Dakota School of Mines and Technology and the high was 71 degrees Fahrenheit.