Midpoint of summer officially occurs on Saturday, August 7, 2021, meaning summer is half over. Depending on how your summer is going, this is either good news or bad news. But one thing is constant for everyone: it is getting darker earlier in the evening. Since the Summer Solstice on June 20, the length of daylight has been getting shorter; a result of the Sun’s direct rays migrating back toward the south.
Summer is when the Sun reaches 90 degrees of longitude, and fall begins when the Sun reaches 180 degrees of longitude. The midpoint, therefore, comes when the Sun reaches 135 degrees of longitude and, in 2021, this occurs during the day of August 7.
Traditional Midpoint of Summer – Lammas Day
While August 7th is the official midpoint of summer, the traditional midpoint of the summer season actually occurs on August 1st, which is marked on some Christian calendars as Lammas Day, one of the four traditional “cross-quarter” days midway between the solstices and the equinoxes.
The name is derived from the Old English “loaf-mass,” because it was once observed as a harvest festival. In fact, Lammas Day comes almost exactly six months after Groundhog Day, the traditional midpoint of winter. Celebrations of Lammas Day include baking of bread, and enjoying a feast with friends and family.
Over the centuries since this tradition took root in Europe, the calendar drifted with respect to Earth’s position in its orbit. So in 2021, the midpoint between the June solstice and the September equinox has changed from August 1st, and its true midpoint—the moment that comes exactly between the summer solstice and the autumnal equinox in 2021—happens Saturday, August 7th. On that day, as seen from the Boston, for example, the Sun will set at 8:07 p.m., with the loss of daylight since June 20th amounting to a little over an hour.
Midpoint vs Midsummer
Midsummer is actually a reference to the summer solstice, the first day of summer. Find out why!
Amount of Daylight is Decreasing…Quickly!
If you think about it, the length of daylight was rather substantial since about the middle of May. And the lowering of the Sun’s path across the sky and the diminishing of the daylight hours was rather subtle during the first half of the summer season.
But during the second half of summer, the effects of the southward shift of the Sun’s direct rays become much more noticeable. When autumn officially arrives on September 22, the Sun for Bostonians will set at 6:57 p.m.—America’s Walking City will have lost 2 hours and 6 minutes of daylight since Aug. 7th.
That comes out to an average loss of 2.68 minutes of daylight per day. That doesn’t sound like much, but it sure adds up quickly: over a span of just one week, it amounts to a loss of nearly 20 minutes of daylight.
So enjoy the last half of the summer season and get in as much of your favorite activities as you can before there’s a chill in the air and darkness wins out over daylight.