Have you noticed? Since Saturday the 21st, the daylight hours have been on the increase. Well, hours may be too strong a word, they’ve only been increasing by seconds each day, but as we move through winter and toward summer it will add up.
Sunrise and sunset for you will change depending on the mountains around you, but “official” sunrise and sunset are based on the horizon, as if the mountains were made of glass. Based on that, Teton Valley had 8 hours and 55 minutes of sunup daylight on December 21. By New Year’s Eve, that will increase to 8 hours and 58 minutes. What are you going to do with all that extra daylight?
Things change quickly as the new year goes on. By the end of January we will have 9 hours and 49 minutes of daylight. On March 19, the first day of spring, the sun will be up more than half of the day, 12 hours and 6 minutes. But wait, there’s more. On June 20. the longest day and the start of summer, we will be up to a whopping 15 hours and 27 minutes of sunshine, and that doesn’t even count the bright skies before sunrise and after sunset. But we aren’t quite the land of the midnight sun at this latitude; the sun will rise that day at 5:42 AM and set at 9:10 PM. (Ok, that’s 15 hours and 28 minutes of daylight, guess it depends on how you round off that last minute.)
Another thing you will notice is that the place the sun rises and sets will change a little bit each day. The sun begins to move farther south in the sky at Summer Solstice and at Winter Solstice it appears to turn around and fly north for the winter. This annual round trip is what makes our mountains and structures like Stonehenge such good calendars once you learn to read them. Before free calendars were available at Corner Drug, ancient times, this was good to know by anyone who wanted to try to plant and grow crops each year.
As the hours of daylight increase, the overall warmth will eventually respond, with several weeks of lag time before things really start to heat up around here. A watched pot. We at Teton Valley Weather will be watching that pot as temperatures rise pretty quickly between February and late July, then start falling again, all in response to the amount of energy we receive from the Sun each day.