Weather-related school closings are a constant source of anxiety this time of year. Sometimes the anxiety is generational: "They never canceled school in my day," parents and grandparents complain when a new snow day gets announced. Sometimes it's regional. D.C. isn't as "flinty" as Chicago, President Obama sighed when schools closed during his first winter in the capital. Northerners watched in puzzlement as two inches of snow crippled Atlanta earlier this week.

A new map from Reddit user Alexandr Trubetskoy (a.k.a. atrubetskoy) is sure to stoke this regional competition. Using data "taken from hundreds of various points from user responses...interpolated using NOAA's average annual snowfall days map," Trubetskoy made a map showing how much snow it typically takes to close schools in the U.S. and Canada. Notice that for much of the southern U.S., all it takes is "any snow" to shut schools down. For the Upper Midwest and Canada, two feet of snow are required for a closure.

Trubetskoy includes the following 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.

Before this map gives Midwesterners a superiority complex, it's worth remembering: School closures say more about an area's infrastructure than the toughness of its citizens. Schools in the South close at the mere hint of snow not because the people who live there are wimps, but because snow is such a rare event—and most cities there don't have a fleet of snow plows the way Northern ones do.

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