Philadelphia hasn’t had snow on the ground on a Dec. 25 since 2009, and in any given year the odds are stacked steeply against having a White Christmas around here. Or anywhere along the East Coast. Or in most of the nation’s population centers. Yet the dream so encapsulated by Irving Berlin’s famous lyrics in “White Christmas” endures.

In the song, Berlin is “dreaming of a White Christmas, just like the ones I used to know.” Rather than memoir, however, the next line suggests this is all a songwriter’s fantasy: “Where the treetops glisten and children listen, to hear sleigh bells in the snow.” After all, Berlin, a Russian immigrant, was raised in Manhattan and was a 20th-century denizen of Tin Pan Alley.

Yet the historical record suggests that both lines could well have been drawn from personal experience — yes, even the sleigh bells.

On occasion, the atmosphere likes to mock the odds, and that likely has something do with the association of snow with Christmas. Certainly, Berlin had a whole lot to do with it — with a whole lot of help, and not just from Bing Crosby and the movie bearing the same title as the song.

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A brief history

The late Tristram P. Coffin, a cofounder of the University of Pennsylvania folklore department and author of The Book of Christmas Folklore, traced the association to the fourth century. The tradition of “Santa Claus” was rooted in the legacy of the bishop of Myra, Nicholas, who died in 342 and later became St. Nicholas.

He is depicted in images as wearing red robes — but keep in mind this is about 17 centuries before selfies The garments, by the way, appear more ecclesiastical and tasteful than the ones worn by the average department-store Santa, but, yes, they are a reddish color. St. Nicholas became revered in northern Europe, particularly in the Netherlands.

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On Dec. 6 every year, according to Dutch tradition, St. Nicholas would appear in the sky on a white horse, for whom children would leave hay in their wooden shoes.

The Dutch carried the tradition with them when they settled in New York state, and writer Washington Irving popularized the image of “Santa Claus” in a satiric poem. But it was another poem, credited to a professor of Greek and Oriental literature named Clement Clark Moore, that bound snow with Christmas with an immutable epoxy.

The formal title of the poem was “Account of the Visit of St. Nicholas,” and its authorship remains a subject of debate. It first appeared in 1836 in the Troy, N.Y., Sentinel. Most people know it as “’Twas the Night Before Christmas,” for one of the most famous first lines in all of literature. To the St. Nicholas narrative, the poem added reindeer and a sleigh that was the equivalent of a 19th-century pickup truck brimming with gifts. Sleigh blades need a friction-free frozen surface as much as 21st-century tires need macadam.

Troy, in the Upper Hudson Valley, is one of the places that has half a chance of seeing a snow cover at Christmas. Those “clipper” systems barreling eastward from southwestern Canada sometimes pass over that area, and the region is close enough to the Atlantic for nor’easter impacts, yet far enough away to evade the warming impacts of onshore winds that change snow to rain.

And in 1836, a Christmas snow cover would have been all the more likely. That was the twilight of the “Little Ice Age,” an era dating to the Renaissance when Europe, northeastern North America, and perhaps other parts of the planet were significantly colder than they are today.

Another rather famous individual writing in that era was one Charles Dickens. In A Christmas Carol, snow adds more than a dash of atmosphere.

The Christmas-snow connection was dramatically solidified with Crosby’s rendering of “White Christmas” in Holiday Inn, released in 1942 and permanently frozen into popular culture with the 1954 movie White Christmas.

You might have noticed that just about every other movie that has a reference to Christmas also includes snow, albeit unconvincingly, as it was in It’s a Wonderful Life, which actually was filmed during an oppressive heat wave.

Cold reality

The odds against a White Christmas — defined as an inch of snow on the ground on the morning of Dec. 25, are stacked 12-1 in Philadelphia, according to National Centers for Environmental Information.

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It just isn’t the snow season yet in the East. Although the sun is at its nadir in the Northern Hemisphere at the solstice, it takes a few weeks for the earth to respond and for the chill to ripen in the upper air, where precipitation forms.

East Coast snowstorms are driven by coastal lows that can import warm air from the Atlantic Ocean.

Cluster snows

In the period of record dating to 1884, using the government’s criterion and record base, Philadelphians have awakened to snow about once every 10 years. However, this has happened in notable clusters followed by long lulls.

It happened five times from 1904 to 1914, and six times from 1959 through 1966, the year that a foot fell on Christmas Eve. That was something of a grand finale, however, as Christmas mornings would be snowless for the next 29 years.

Similarly, New York had four quite significant snow-covered Christmas days from 1896, when Berlin would have been 8, until 1912, with four more from 1917 to 1930. But then nothing until 1945. So when he wrote the song that debuted in Holiday Inn and became a wartime sensation — the nostalgic component likely was more than an affectation.

And regarding those sleigh bells, 1898 and 1904 videos shot by Thomas A. Edison Inc. now in the possession of the Library of Congress show horse-drawn sleighs dashing through the snow in Central Park.

If sleigh bells and snow are not on your Christmas wish list, may your days be merry and bright.

This article was adapted from Anthony R. Wood’s Snow: A History of the World’s Most Fascinating Flake, published in December 2020 by Prometheus Books/Rowman & Littlefield.