Among the regular visitors to the plains winter is the Alberta clipper — a fast-moving low-pressure system born over the Canadian prairies and swept southeast on a plunging jet stream. Named for the swift sailing ships of old, the clipper lives up to its name, racing across the region in a day and leaving a quick shot of snow and a hard plunge in temperature in its wake.

A Fast Rider from the Prairies

The clipper is not usually a heavy snow-maker; moving fast and starved of moisture on its overland path, it typically drops only a few inches. Its real signature is the cold and the wind behind it. As the clipper passes, the temperature can fall precipitously and the wind swing sharp and biting, setting up the very conditions for a ground blizzard on the fresh snow.

From the almanac's reckoning:

• The Alberta clipper forms over the Canadian prairies and races southeast.
• It brings light snow but a sharp drop in temperature and wind.
• Clippers can arrive in quick succession through the winter.

Forecasters watch the northern skies for these fast riders all winter long, for they can string together in quick succession, each adding its cold to the last. The almanac counts the Alberta clipper among the workhorses of the plains winter — quick, cold and reliably unwelcome.