It’s the first day of Astronomical Summer, as opposed to the first day of Meteorological Summer, which is June 1st.
I know this because Weatherman extraordinaire, Tom Skilling, likes to explain the difference between astronomical and meteorological with every season change.
I also know that all this day really signifies is that from now until Astronomical Winter the amount of sunlight we receive is getting shorter. Crap.
If you want the same amount of sunshine for your brain every day, subscribe to my YouTube channel or “Like” “Songs By Andy” on Facebook!