Warmer, drier summer season lies ahead
Our first day of “astronomical” summer, the summer solstice, began on June 20 at 2:44 p.m. That was the day when the sun angle was the highest in the sky across the Northern Hemisphere.
Typically, much of the Northern Hemisphere will experience the highest number of daylight hours on the first day of summer. However, the exact number of hours and minutes will have some slight variances across most towns and cities due to differences in elevation, terrain and proximity within the time zone.
In Coeur d’Alene, our longest day was on Friday, June 19, with a total of 15 hours, 59 minutes and 58 seconds of daylight. Now, the daylight hours are beginning to shrink, but most of us won’t know the difference for a while. In fact, for today, June 22, also my 57th birthday, our time of daylight lost 20 seconds since June 19.
Last Friday, the sun’s rays were directly overhead at 23.5 degrees North latitude in the Northern Hemisphere, called the Tropic of Cancer. This region of latitude runs through Baja California, Mexico, Egypt, India, Saudi Arabia and southern China. The “summer solstice” is named the June solstice as the Southern Hemisphere, by complete opposite, experienced its first day of winter.
However, our longest day of the year is normally not the warmest due to a lag effect. On June 19 and 20, Coeur d’Alene’s average high temperature is 76 degrees. Our warmest period, based on long-term averages, normally occurs from late July through early August, as the normal high is 88 degrees. Right now, our planet absorbs more sunlight, but it takes about a month for the earth to release it.
On the summer solstice, there is continuous sunlight over the Arctic Circle, which is above 66.5 degrees North Latitude. According to an article in Reader’s Digest, in northern Iceland — a place I would love to visit one day — there is a spot where one can sit on a cliff that overlooks the sea and watch the sun “not set.” Apparently, “the sun will dip down to the horizon, brushes the water and then starts to rise again.” By contrast, it’s completely dark in that part of the world on the first day of winter.
As the days progress into September, by the first day of fall, the sun’s rays will be directly overhead at the Equator (0 degrees latitude) and then at the Tropic of Capricorn, 23.5 degrees South latitude in the Southern Hemisphere on our first day of winter, the Winter or December Solstice. By the way, the first day of fall arrives on Sept. 22, and that is the date when every location on the planet receives approximately 12 hours of day and night.
As I’ve mentioned in other columns, as our planet orbits the sun, we are farther away from our star by about 3 million miles at this time of year than during our winter season. The Earth’s tilt of 23.5 degrees is what contributes to our seasons. Right now, our planet is tilted toward the sun in the Northern Hemisphere and away from the sun in the Southern Hemisphere. During our winter, it’s the opposite, as we’re tilted away, so the sun angle is much lower and we’re still experiencing those cold temperatures despite being about 3 million miles closer to the sun.
The article from Reader’s Digest points out other interesting facts about the summer solstice. The word “solstice” originates from the Latin word “sun stand still.” In our solar system, all planets will have a summer solstice. On Mars, it occurs about every few days after ours in June. On Uranus, there’s only one summer solstice every 84 years.
According to History.com, the summer solstice was the start of the New Year on some ancient Greek calendars. Ancient civilizations also built amazing structures to acknowledge this time of year. Mayan observatories and temples were built specifically to observe the sun. Stonehenge, perhaps the world’s most famous prehistoric monument, is aligned with the direction of the sunrise on the summer solstice. In Egypt, the sun sets directly between the Great Pyramids when viewed from the Sphinx. Ancient astronomical knowledge of the seasons is truly amazing.
• • •
In terms of our local weather, the first half of June certainly didn’t feel like late spring or summer as temperatures were below normal. There were 6 days with highs only in the 50s in Coeur d’Alene. June 9 was the coolest with a high of only 52 degrees. As of late Sunday, our June precipitation was slightly above the normal of 1.97 inches.
However, the overall weather pattern will be turning much drier and warmer. There may be some showers or an isolated thunderstorm at the end of the month or early July. It will be one of those summer patterns where it won’t be “rainless,” but it will just “rain less” than normal.
• • •
Contact Randy Mann at randy@longrangeweather.com