Higher sun and longer daylight

7 years ago

In two weeks, when my next column comes out, it’ll be Feb. 21, and we’ll be one-third of the way to high summer and will have gained 2 hours and 4 minutes of daylight since the winter solstice.

Each year, around Dec. 21, our lowest sun angle of the year occurs, with the sun a mere 20 degrees above the southern horizon at the midpoint of its trek across the sky. The best way to think of the sun’s path across the sky is to think of a parabola (envision the St. Louis Arch). The top of the arch is solar noon, the midpoint of its journey, from sunrise to sunset.  So again, around Dec. 21, this midpoint is only about 20 degrees above the southern horizon, whereas on June 21, the first day of summer, it’s about 67 degrees above the southern horizon.

Let’s do a field exercise to better envision this. First face south. Now, think of 90 degrees above the southern horizon as raising your hand to ask a question. Your arm is pointed straight up at the sky. Now slowly lower your arm, keeping it extended, until it is halfway between “asking a question” and straight out, parallel to the ground. Your arm is now 45 degrees above the southern horizon. So to use your arm to see where the sun would be at its lowest, in late December, lower your arm further, from 45 degrees, until it is halfway between the 45-degree position where you were, and having it being held out directly in front of you, parallel to the ground. Now you are at 22.5 degrees above the southern horizon, pretty close to that Dec. 21 lowest position.

But now we have been coming off that lowest sun at solar noon position for six weeks, with the sun gaining altitude above the southern horizon each and every day. By the end of February, you’ll feel the increase in the warmth of the sun on your face, even on a cold day, if you are out of the wind. Now, to see where the sun will be in the sky on the summer solstice, June 21, at solar noon, which again is the midpoint of its daily trek across the sky, get your arm back to 45 degrees above the southern horizon. Now lift it upwards, halfway between the 45-degree position and having it pointing straight up at the sky. Now you are at 67.5 degrees, pretty close to the solar altitude above the southern horizon at solar noon, on the summer solstice.

Higher sun angles will melt a minor snowfall more rapidly. A lot of people will go out and just by muscle memory, clear their car of a few inches of snow that may have fallen overnight. But this is one of the ways in which you can use your knowledge of weather. If you don’t actually have to leave for a couple of hours, and if your car is parked in the sun, once the overnight snow has moved on, let M. Nature do your snow clearing for you.

Here’s another way to minimize your work. If you hear that snow will be changing to freezing rain (that’s the clear ice glaze), and assuming you don’t have to use your car for a while, leave the snow on it. The reason to do this is that your snow-clearing efforts will be much easier if the ice doesn’t have a chance to bond to the glass. And that nice layer of snow that you leave alone, will have the glaze on top of it, rather than coating your windshield. Doing it this way will make your morning car-clearing task a breeze.

Switching gears briefly, attention must be paid. Yesterday, Feb. 6, was the 40th anniversary of the onset of New England’s famed Blizzard of ’78. Boston saw winds gust beyond hurricane force, with a peak gust of 79 mph. The drifting was very severe, and to underscore the importance of keeping your tailpipe clear of snow, if you are ever stranded in a winter storm, please read this excerpt from The Boston Globe:

“… soon the occupants of some 3,000 cars and 500 trucks became stranded in rapidly-developing snow drifts along Rt. 128. Fourteen people would die from carbon monoxide poisoning as they huddled in their snow-trapped vehicles.”

This very powerful storm produced large, battering waves. Hundreds of homes were demolished on the Massachusetts coast.

Two to three feet of snow was commonplace, with NW Rhode Island reporting as much as 50 inches.

For southern New England, the Blizzard of ’78 is pretty much the benchmark against which all southern New England winter storms are measured.

Here in Maine, early February saw a couple of very notable records. February 1st was the 63rd anniversary of the coldest temperature on record at Caribou, 41 degrees below zero on February 1st, 1955.

And down in Bangor, last Friday, Groundhog Day, was the 42nd anniversary of the rapid flooding of downtown Bangor by a true storm surge flood, as a very intense low pressure system sent a tremendous surge of ocean water up Penobscot Bay. Google “Bangor Flood 1976”, and you won’t believe some of the images. The center of the low tracked across midcoast Maine, and then up through northern Maine, passing west of Caribou. This put the city on the warm side of the circulation, which sent the temperature all the way up to 49 degrees. Meanwhile, the barometer was crashing, with the low reading of 28.26” being the lowest on record at Caribou.

Ted Shapiro holds the Broadcast Seal of Approval from both the American Meteorological Society and the National Weather Association. An Alexandria, Va. native, he has been chief meteorologist at WAGM-TV since 2006. Email him at tshapiro@wagmtv.com.