By now, most of us have seen our first snowflakes of the season.
Depending on where you live, it might have been cosmetic or perhaps more significant than that. While everyone knows what snow is, I detect some confusion when it comes to describing snowfall.
During the next few months, we'll no doubt hear the frozen crystals referred to as snow, snow flurries, snow showers and snow squalls but these are not interchangeable.
Let’s start with snow. Snow refers to the thing itself - frozen water vapour that falls in flakes. Snowfall typically describes an event that lasts for a period of time; it is commonly associated with some accumulation of snow on the ground.
Snow flurries could be described as the rain equivalent of drizzle; flakes here and there that don't amount to anything on the ground. Let’s think of them as harmless or very light snow.
Then we have snow showers. These could be seen as the winter version of rain showers. Snow showers mean that you'll get short bouts of snow; it can be snowing for an hour, then stop for two. It also means it might be snowing in some places around the area, but not others.
Finally, the infamous snow squalls.
There are two types of snow squalls. The first, and most common if you don't live close to a large body of water, is a frontal squall; the vertical lift is triggered by a frontal line. In this case, the snow squall is a short but ferocious burst of heavy snow and strong wind, usually lasting less than an hour.
The other type of snow squall is one that we know far too well here on the East Coast; it’s wind-driven and fuelled by warmer water.
These squalls begin with a strong wind carrying cold, dry air across a warmer body of water. They gather moisture over the relatively mild water and dump snow when they make landfall. The stronger the wind, the farther inland the snow will carry. Individual squalls of heavy snow can sit over one small area for several hours, even days; nothing changes until the wind direction does.
Knowing which way the wind blows is always very important when you live by the water. Perhaps a weather vane would be a good gift idea for that hard-to-buy-for person on your Christmas list.
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Cindy Day is the chief meteorologist for SaltWire Network