Far out details on space and snow

4 years ago

Dr. Jessica Meir, a native of Caribou, recently described the indescribable. As she was preparing for her space walk, she looked down at her boots, and waaaay down below, she saw her home planet through the darkness. To think that she actually saw it, from the vantage point of space, is truly remarkable.

Of course, the International Space Station is in space, but it is not as far out there as you might think. In fact, it you drove from Caribou to Augusta, it would be about 250 miles. If you went straight up instead, that’s about how high the ISS is, about 250 miles. Here’s a question: how much farther would Dr. Meir need to go to get to the moon? The answer is startling: almost 1,000 times farther. The moon is about 240,000 miles from Earth. Thinking of it yet another way, she is orbiting the Earth at an altitude of about forty-five Mt. Everests above sea level.

Now let’s switch gears and dig into some winter stats. This first one always surprises people. What do you think the record is for most consecutive days at Caribou with a daily high temperature below 0 degrees Fahrenheit? Many longtime County residents will remember weeks of subzero temps. The actual record? Four days. That’s right. It happened from Jan. 8-11, 1968.

How about most snow in a two-day period? I use two days, since that covers cases where a snowstorm straddles two calendar days. That number is 29 inches on March 13 and 14, 1984. Second place is the Christmas blitz of 2005, when almost 28 inches fell at Caribou on Dec. 25 and 26.

Coldest temperature on record at Caribou: 41 below, back on Feb. 1, 1955. Coldest on record in The County: 50 below at Big Black River on Jan. 16, 2009. That reading set a new state record, eclipsing the 48 below in Van Buren in 1925.

How about the earliest high temperature that remained below zero. That would be Dec. 9, 1976. The latest subzero max? March 11, 2017. I remember that day well. It seemed so odd to have such a high sun angle (for that time of year), and and yet have it still be so cold.

Now let’s look at a bit of terminology. A winter weather advisory is issued if snow accumulation is expected to reach at least four inches. A winter storm warning is issued if snow accumulation is expected to reach seven inches in 12 hours, or 10 or more inches in 24 hours. 

But if snow is the only precipitation type expected, no NWS advisory will usually be issued if only 1-3 inches of snow is expected; however, the projected accumulation amount will be included in the text of the forecast. But again, if less than 4 inches, no advisory will hit your phone. 

Advisories and warnings can also be issued for other precipitation types. In winter, other than snow, we have sleet and freezing rain. Sleet starts as snow at cloud-level, which then melts into raindrops, as the flakes fall into an above-freezing layer of air. The rain then re-enters below-freezing air on the way to the ground, and comes down as small pellets of ice, about the size of BBs. Freezing rain goes through the same process with one key difference. The sub-freezing layer of air in contact with the ground is so shallow (does not extend very far above the ground), that the raindrops do not have time to freeze into ice pellets, instead they freeze on contact, creating a dangerous, icy glaze. When looking at winter’s most dangerous hazards, freezing rain is way up near the top of the list. It’s virtually impossible to drive on a glazed-over road. 

When there is a heavy glaze of ice that brings down power lines and trees, it is called an ice storm. There is a National Weather Service product called an ice storm warning. Hope you don’t ever hear those words, as ice storms are very destructive. Just ask anyone who went through the ice storm of 1998 downstate.

If there is one particular winter word which gets everyone’s attention, it would have to be “blizzard.” Most people think that a blizzard warning automatically means a whole lot of snow, but the definition, surprisingly, does not include snow accumulation. It is, “falling and/or blowing snow, that limits visibility to 1/4 mile or less, with winds of 35 mph or stronger, with these conditions all lasting for at least three consecutive hours.”

Of course we certainly can get lots of snow with blizzard warnings in effect. I still remember January 2018, and I’ll bet you do, too.

Back when I was a weather-fascinated kid, growing up in the D.C. area, the National Weather Service, which was called the U.S. Weather Bureau before 1970, would issue travelers advisories if winter weather was expected to cause region-wide slick travel, irrespective of forecast amounts. I though this was an excellent product, as it alerted folks to the thing they cared most about: are the roads going to be slippery or not? 

I like to use that terminology (travelers advisory) in my forecasts.

I can’t close without mentioning the big windstorm that opened this month. I’ve heard from several people who have have lived on their property for a number of years, and had never had to clear that much treefall. The highest wind gust I saw was 56 mph in Frenchville. I think one of the things that exacerbated the problem was the saturated soil following the heavy rain; the roots on some trees were just not able to “grab.” And some trees were just snapped off. 

By the way, that morning, on the 1st before dawn, Caribou saw a reading of 68 degrees, tying the warmest temperature on record for the month of November, and they’ve been keeping track for 80 years. The last time it was 68 in November was also on the 1st, back in 1956, sixty-three years ago.

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.