The Alberta Clipper is a quick moving storm from Canada that can be easily identified as low pressure systems originating somewhere in Southern Canada. More specifically, they form over the Providence of Alberta, but can start as far west as British Columbia or as far east as Saskatchewan. The fast moving nature of these storms means they ‘clip’ your region.
HOW THEY FORM
Moist air off the Pacific Ocean flows eastward into the Northwest United States just as cooler air in Canada moves southward. These two air masses combine and a rotating surface low can form. That low moves quickly from west to east toward the Dakotas and the Great Lakes.
This storm system is accelerated by a quick moving jet stream aloft. It it not particularly large in scale and the fast moving nature prevents from these storms bringing significant snowfall. Usually around 1-3 inches is expected, but if the snow ratio (liquid to ice) is high, then amounts can be inflated. This can happen if temperatures are very cold and stay well below freezing through the whole event.
- Snowfall on the order of 1-3″
- Strong winds, gusting 40 mph at times
- Cold air behind the system
If these storms strike just at the right time, like during a morning commute and early in the season, they can catch some off guard that may not have seen the forecast. These storms can sometimes occur during the fall and spring seasons and bring rain showers, but they are more common in winter with a larger gradient in temperature across state and country borders.
Sometimes these storms can be called Saskatchewan Screamers, but they are essentially the same thing.