How Much Snow Before America Cancels School?

Decades of national news have reinforced in each of us the maxim that one man’s snow flurry is another man’s natural disaster. We New Englanders have long taken smug pleasure in watching a few inches of snow flummox city officials in Washington D.C. “Why do they get school off for a light dusting?” we grumble, as our cars skid and fishtail their way to class through 10 inches of powder.

This phenomenon reasserted itself last week when two inches of snow brought the city of Atlanta grinding to a halt. So Reddit user atrubetskoy set out to visualize and quantify the phenomenon. Using data “taken from hundreds of various points from user responses and interpolated using NOAA’s average annual snowfall days map,” the map shows the average amount of snowfall it typically takes to cancel school.

Massachusetts, as it turns out, isn’t the most hardcore. For us, about 12 inches typically gets the job done. Move inland and further north, and you need closer to 24 inches. Meanwhile, vast stretches of the American South and California will cancel for “any snow” at all.

There is, of course, a lot that goes into the decision to cancel school. The temperature, the wind conditions and chill, and the timing, for instance. A six-inch snowfall at 4 a.m. can be too difficult to clear in time for the morning bus routes, while a foot of snow at 6 p.m. offers cities enough time to clear the roads. The map became enormously popular this week, so atrubetskoy offered some more clarifications:

In much of the Midwest and Great Plains, school closing often depends more on wind chill and temperature than on snow accumulation (“cold days”). Thus, this map may be misleading in those areas.
Many jurisdictions in California and other western states have significantly varied snowfall, depending on elevation. This makes it difficult to find an “average” number, or often makes it misleading.
Urban areas like Chicago and New York have more resources to clear snow and often need more to cause closings.
Clarification: The lightest green says “any snow” but also includes merely the prediction of snow.
Clarification II: This is snow accumulation over 24 hours/overnight.
Hawaii does get snow! Just… not where people live.

There are a million more regional idiosyncracies and, local pride being what it is everywhere, people are chiming in with them on the Reddit thread. The catch-all explanation for the map’s general trends is, of course, that cities that expect snowfall provide the budget and infrastructure to clear it, which means they can handle more before canceling becomes necessary. They have plows and snow tires and iron wills. The rare two inches in Atlanta aren’t worth maintaining a fleet of plows. So it’s not that they’re wimps. It’s just a practical calculation that they don’t need to prepare for snow in the same way, and if that means missing a day or two here and there, so be it.

But, of course, that doesn’t mean we can’t laugh bitterly at them while we shovel our cars out at 6 a.m. to get to the bus stop.