It’s that time of year, that month that is the dividing line between winter and spring, when hope springs eternal but car shocks might not.
March is the month when temperatures fluctuate above and below the freezing mark (32ºF). Of course, the further south one goes that is more above freezing than below, but the fact remains that those oscillations are what matters most. Because simple water, in its expansions and contractions, can kill.
To that point, March might be the month of the greatest number of pothole formations (although, can you call it “formation” when what it is is a void?). But let’s remember that potholes are a result, not a cause. So let’s name this time for what it is: National Freeze-Thaw Month.
Potholes and falling bricks in March
Because when something melts and then freezes again in spaces like cracks, hard objects pry apart. Of course, we most often think of that in terms of pavement – when cracks in asphalt are pushed apart by water that turns to ice overnight, only to be filled up again when the sun shines the next day, then frozen apart further when nighttime temperatures drop.
There is another phenomenon affecting cities called “Jack Frosting,” which refers to that moment when rain becomes freezing rain in major cities like New York. The frozen precipitation gets into the cracks in building facings and façades. The physics of the little moisture crowbars are such that portions of concrete, brick, terra cotta, and mortar come loose and fall – into alleys, onto sidewalks, bouncing off canopies, and sometimes hitting pedestrians and cars.
Note the pedestrians and motorists are already busy avoiding puddles, ice patches, and potholes, looking down to protect themselves – and not at all looking up.
March is the cruelest month
December, January, and February are typically much colder, and consistently so. But March is when the tease of spring is abruptly met with the icy response of a winter that came back, like the guest who left their hat at the party and rudely knock on the door after the party hosts’ turned their lights out.
T.S. Eliot wrote in his poem, “The Waste Land,” that “April is the cruelest month.” If you live in Minnesota, that clearly is true. Less so if you call Paris (France) home. But March, the time of the most freeze-thaw action in the temperate northern hemisphere, pretty much makes mincemeat of April.
Be careful out there – look up, down, and everywhere else. Potholes and Jack Frosting are out to get you.
