Meteorological Seasons

October 6, 2020 // Article by: Bobby Bianco

Do you know the term: Meteorological Seasons?

Well, they are the dates that meteorologists use to better define the heart of each season. So let's get into the details on what is actually going on here! Of course, meteorologists still know and use the astronomical seasons as well, but there are some unique reasons why we have this set of seasonal dates.

Different from the equinox or solstice, meteorological seasons occur on the same day each year. They are broken down into 4 month intervals which can make it simpler to remember. The dates of the seasons, in order from spring, summer, fall, and winter are as follows: March 1, June 1, September 1, December 1. It can be a bit confusing to think that there are 2 sets of seasonal dates, but meteorological seasons are set strictly for climatological and even agricultural reasons.

On the other hand, the "normal" astronomical season dates are due to the Earth's tilt,which was explained in the blog "Equinoxes and Solstices". To touch on agriculture, these specific dates for the start of meteorological seasons can influence when farmers should plant their crops, harvest them, etc. Now getting back to climatology, which in simple terms means "past weather data", there are trends in temperatures from the past 50, 100, or more years. From this data, we can determine when temperatures usually increase and decrease. However, just because we get to these dates, this does not mean they are rock solid every year and temperatures will immediately get warmer or colder. There are other meteorological factors that can go into seasonal changes as well, which can prolong or end seasons, but we will refrain from going into detail. 


While looking at past temperatures for each month/season, the dates above are the ones that usually begin a trend into that season. For example, by March 1st, temperatures typically begin to increase as spring begins, then June 1st is usually when we begin to have more "summer-like" temperatures. These are not forecasts for what's to come, but climatologically when the temperatures begin to shift towards the next season. 

So, the next time "Meteorological fall, spring, etc." is tossed around in conversation on the news or by a meteorologist, you’ll know when these seasons begin and why they were created