Summer begins in the Northern Hemisphere on Wednesday, June 20, 2012, at 7:09 P.M. (EDT). Yes, after you get home from work. Rather fitting.
The timing of the solstice depends on when the Sun reaches its farthest point north of the equator and that occurs on June 20 or 21 in North America.
Summer is the beach, nicer weather, vacation, relaxation, flowers, and hot, humid days, twinkling lightning bugs and it is mosquitoes, horseflies, and ticks attacking us, and deer and bugs attacking our gardens.
Solstice is from the Latin solstitium, from sol (sun) and stitium (to stop), because at one time the belief was that the Sun stopped at this time and again at the winter solstice.
If you watch the movement of the Sun during the year (and most modern people do not), you notice that the Sun is higher in the sky throughout the day now. Come winter, you would note the opposite occurs. On the summer solstice, the Sun is directly overhead at its most northern point at “high-noon” on the summer solstice. There will be more sunlight in the Northern Hemisphere on this day than any other – even if it is cloudy in your part of the world.
The original Roman name for this month was Junonious, from the Great Mother Goddess Juno. (Her counterpart for the Greeks was Hera.) The Summer Solstice was once much more important to religions and cultures around the world. It was the sacred time to goddesses of fertility, marriage, and love, and on the other side, it was when faeries, elves, and the supernatural was very active.
I was confused when I first read Shakespeare’s Midsummer Night’s Dream because “midsummer” seemed too early. Shouldn’t it be in July? In the Northern hemisphere, the period around the June solstice is known as midsummer, and Midsummer’s Day is June 24, about three days after the solstice itself. So, Midsummer Day refers to the period of time centered at the summer solstice, but more often refers to specific European celebrations that accompany the actual solstice, or that take place on a day between June 21 and June 24, and the preceding evening. The exact dates vary between different cultures. Midsummer is especially important in the cultures of Scandinavia, Estonia and Latvia where it is the most celebrated holiday apart from Christmas.
You might expect the solstice to be the hottest day of the year, but our atmosphere, land, and oceans are still cool from winter and spring and absorbing part of the incoming energy from the Sun. As the land and, especially, oceans release stored heat later in the summer, we will get our hottest temperatures. That is what is called seasonal temperature lag. Enjoy the lag while you can!