Christmas Eve of 2009 was not exactly a traditional one for my husband and I. We both worked rotating shifts as forecasters with the National Weather Service, so it was not unusual for one or both of us to work a holiday. We opened our gifts together in the afternoon, then packed overnight bags, sleeping bags, and our dog … and we drove through blowing and drifting snow into work.
It was a blizzard, one that was well forecast and yet one that made meteorologists anxious because of its timing. We worried that people would still try to travel, despite the deteriorating conditions, to keep their holiday plans intact. Of course, here we were, also driving. We left earlier than planned, and we still had to drive through drifting roads to get to work. We got there before the worst of it struck, though. Only one of us was scheduled to work that evening, with the other on the Christmas day shift. We came in with the intent to be snowed in at work so that we would be able to relieve our coworkers from their shifts. The staff took turns napping on old cots in the managers’ offices, then doing the work of forecasting the weather, communicating the hazards, and examining the snow and wind observations.
It’s not uncommon for National Weather Service’s meteorologists to sleep at the office during the worst of the weather, allowing several folks to rotate through the shifts while others get rest during weather that leaves them stranded. Offices often have cots or inflatable mattresses, and they are equipped with microwaves and refrigerators for food. It’s a sacrifice that folks on staff make willingly to keep themselves and the people in their areas safe.
The blizzard raged for over a day. We eventually went home in the late afternoon on Christmas Day, nearly getting stuck in a drift on our neighborhood roads on the way home. The blizzard was one of three that struck the Plains states in December 2009, kicking off a winter that was the most severe in generations.
What a Blizzard Is (and Isn’t)
By the National Weather Service definition, a blizzard occurs when falling or blowing snow, combined with sustained winds or frequent wind gusts of at least 35 mph, reduces visibility to a quarter mile or less for at least 3 consecutive hours.
There is no requirement for how much new snow falls (if any), nor is there a requirement for how cold it gets (there used to be, many decades ago). That there is snow in the air is a must. That the wind is blowing is a must. That together, they reduce visibility to dangerously short distances is a must. Falling snow by itself doesn’t cut it, no matter how heavy the snow is.
Heavy snow alone does not make a blizzard. The wind is such a critical factor in what makes a blizzard dangerous that it is irresponsible to ignore the distinction.
Blizzard History
Being a bit of a word nerd, I delight in the history of the word “blizzard” as used to describe snow and wind. The word originally stemmed from more violent applications - a series of violent blows, or a blizzard of gunfire. The first documented use of “blizzard” to describe a snow and wind storm came in a newspaper article in Estherville, Iowa, on April 23, 1870, but the word reached popular use during the Hard Winter of 1880-1881. The word ramped up in usage pretty quickly through the rest of the 1880s, and now it remains in our everyday and scientific language.
The Danger of Blizzard Exposure
Snow brings hazards in its own right. On roads and sidewalks, snow can make surfaces slick or, if it’s deep enough, block them altogether. Sticky, wet snow can load tree branches and power lines past their tolerance and knock them down. Very heavy snow can obstruct visibility, even without the wind.
When the wind is in play, though, the threat escalates. Wind makes snow drift and pile. A road can be mostly blown clear of snow, and then a drift higher than the wheel wells slithers across as a trap. Wind rocks the trees and power lines, sometimes shaking them loose and sending them tumbling. Wind sends snowflakes adrift on not just the straight winds themselves, but all the eddies and curls that wind makes when it moves around obstacles like cars, buildings, trees, overpasses, signs, and fences. The effect is disorienting, because even a straight wind doesn’t look straight when every curl and swirl is decorated with reflective snowflakes. Drifted snows mask ditches, posts, and landmarks.
Even if there is no temperature threshold for blizzard conditions, it is typically below freezing in a blizzard. Combined with winds of 35 mph or more, wind chills near or below zero are common. And dangerous.
Now, imagine someone out in a car on the interstate in open prairie during a blizzard, against all advice from authorities. With snowflakes flying past the windshield like they’re in warp mode through a star field and snow drifting over the road, the edges blur into a sea of white, and “straight ahead” loses meaning. The driver strains, looking harder for guidelines like the mile markers, the white line along the shoulder, or the drop-off to the ditch to make sure they’re on the road. White wisps stream across the road, leaving drifted patches where the snow is a bit deeper than the rest of the road. The driver is only going about 30 mph, even on the interstate. But they have places they feel they have to be. Work won’t let them take the day off, or that hotel is nonrefundable, or they promised they’d come visit for the holiday.
They don’t see how deep the next drift is until they’re already barreling into it. The drift grabs hold of the tires on one side of the car, sending it whirling around and into the ditch. It happened so fast that the driver hardly had time to even draw a breath. Here they are, between exits on the interstate, way off the side of the road. At least they’re far enough off that probably nobody will come barreling down the road and hit them.
Now they have a choice. They’re a few miles from the next exit. Do they take the chance to walk it, or do they take the chance to stay in the car? They have a granola bar and half a cup of lukewarm coffee they grabbed on the way out. They do have a coat, hat, gloves, and boots, at least. No blanket, though. The gas tank is half full. It was such a short trip - just an hour, maybe, in good weather. Neither choice is great. If they stay, they could get snowed in deeper, and it could be hours or maybe even tomorrow until someone can get to them, even with a cell phone to call for help. If they walk, they expose themselves to the elements, and it’s not always easy to walk in a blizzard. That exit ahead is to the west, walking into the wind, and it’ll feel like a giant hand is pressing against their chest. The wind will blow straight into their face, except where it catches swirls and eddies. The drifts are getting pretty high, and it’s impossible to see lights from anywhere with visibility so low.
They stay in the car, call ahead to their destination to say they aren’t going to make it, and then call 911. And then, they wait.
And that is why meteorologists and first responders want folks to stay off the roads during blizzards (or, really, any fierce wintry weather). Blizzards are much better spent cozy indoors, with blankets and cups of warm beverages, safe from exposure to the elements. And I can honestly say from experience that I’d rather be stuck at work, sleeping on a cot and eating a microwave meal on Christmas Day, than stranded on the roads or outside with no clothesline to guide me safely back to my door.
This Month in Wilder Weather History
December 25, 1880: The Ingalls family experienced their own Christmas blizzard as one of the winter’s many blizzards arrived in De Smet, Dakota Territory (South Dakota), in the afternoon or evening on Christmas Day during the Long Winter of 1880-1881. By December 26, observers reported precipitation (snow) all around De Smet, including in Omaha, Minneapolis/St. Paul, Yankton (in far southeastern South Dakota), Fort Bennett (under present-day Lake Oahe in central South Dakota), and Fort Sisseton (in far northeastern South Dakota). Temperatures on Christmas Day were in just the single digits in eastern South Dakota, with lows in the single digits to teens below zero. Blizzard winds would have made wind chills near -30 degrees very likely.