Is the storm over? Maybe not
Winter. Nine feet of snow. And that’s just our average. In the record snow season of 2007-2008, 16-1/2 feet buried Caribou. And even in the lightest season on record (records at Caribou go back to 1939), two winters after the snow barrage, Caribou still had nearly six feet of snow. Such a total is unimaginable to someone (me) from one of the southern states (Virginia), where, in my hometown of Alexandria, we average just over one foot.
Here’s something else that’s unimaginable: 56 feet of snow as your average. But such is the case at the Paradise Ranger Station on Mt. Rainier, Washington state. Washington also holds the record for most snow in the U.S. for a season at a staggering 95 feet. If you had that on the ground all at once, it would be nearly as high as a 10-story building. If you were wondering, the deepest snow on the ground record for the U.S. is 37-1/2 feet, back in 1911, in Tamarack, California.
As we ready for winter, there are a couple of things I’d like you to know about winter storm warnings (when snow is forecast to be the only precipitation type; that is, no sleet or freezing rain or rain mixed in). Winter storm warnings are often linked to the expected beginning and end time of the snow accumulation, and organizations sometimes mistakenly reopen once a winter storm warning expires. However, if the snow is light and fluffy, the most dangerous part of the storm may be yet to come if wind kicks up on the backside of the storm, with blowing, drifting and whiteouts. There are separate warning products that cover these hazards, but again, the point to remember is that sometimes a Winter Storm Warning may expire prior to the arrival of the worst post-storm visibility.
It is critical for decision-makers to drill down into the forecast details, because winds gusting into the 30s (mph), with a fluffy snow already having fallen, is a recipe for disaster. So on whiteout days, if you are not taking someone to the hospital, there’s really no good reason to be out on the road. Plus it helps the plow operators when they don’t have to deal with traffic. So everyone wins — you stay safe and they can tend to the roads.
Let me say a bit about snow ratios. The “standard ratio” you may have grown up learning was probably that 1 inch of rain equals 10 inches of snow. But the consistency of the snow varies tremendously from storm to storm. I have seen snow fluff out to an incredible 40-to-1 ratio. This means that one inch of water would produce 40 inches of snow. The higher the ratio, the more fluffy the snow. Wind plus high-ratio snow is a bad combination, as it can lead to blinding conditions in open country.
Without even hearing whiteout reports, you can actually do a check before leaving your dooryard to determine if you might encounter them. If it has snowed, and the snow is so fluffy that it’s hard to make a snowball, and if the tops of the trees are swaying in your yard, even if you are not observing blowing snow at your location, just assume there will be blowing snow, along with potential whiteouts, when you travel across the open countryside. Whiteouts are one of winter’s most dangerous hazards, and they always have to be treated seriously. After all, how well can you drive with a blindfold on?
Just about everybody thinks a blizzard means a whole lot of snow. Turns out, though, that a blizzard warning can be issued without any new snow being expected. Here’s the definition: Winds of 35 mph in falling OR blowing snow, limiting visibility to one-quarter mile or less, and lasting for at least three consecutive hours.
If you would like to know about easy-to-read clues in advance of an approaching winter storm, along with the most common weather hazards we face in Aroostook County, join me for a talk at the Francis Malcolm Science Center this Saturday, Nov. 2, from 3 to 4:15 p.m. Admission is $5, with all proceeds going to the center’s science education outreach. Seating is limited. For more information, or to make a reservation, call them at (207) 488-5451 or email email@example.com.
Hope to see you there.
Ted Shapiro holds the Broadcast Seal of Approval from both the American Meteorological Society and the National Weather Association. An Alexandria, Va. native, he has been chief meteorologist at WAGM-TV since 2006. Email him at firstname.lastname@example.org.