An Alberta Clipper is a winter storm that has its origins in western Canada, and usually over the province of Alberta, hence its name.

Track of a typical Alberta Clipper

Because they develop over cold Canadian land, Alberta Clippers tend to be moisture-starved. They generally don’t have any large bodies of warmer water to tap into as they develop, and so they remain smaller in size, and contain little moisture as compared to Nor’easters, which can tap moisture from the Gulf of Mexico and the Atlantic Ocean.

Despite their lack of moisture, Alberta Clippers do not necessarily lack energy, and can affect the weather of Western Massachusetts in a variety of ways. Their impact can range from a nuisance system bringing a coating to a couple inches of snow, on up to a moderate, or even major snowstorm.

Normally, though, these are very light snowstorms for Western Massachusetts. They tend to ride a cold frontal boundary that drops into the central U.S., which suppresses these storms south of the Southern New England coast. This keeps us on the northern and western (i.e. cold) side of the storm, resulting in snow. At times, if enough Arctic air is in place, they can even pass to our north and still give us snow (with no change to rain), as we saw a couple times in the depths of the Winter of 2013/2014.

Occasionally, these storms will reach the Mid Atlantic coast, and strengthen rapidly, if conditions are aligned. If this happens, Western Mass can sometimes see more snowy weather than normal, on the order of a 3-6” moderate snowfall. There are rare circumstances where these storms can slow down because of upstream blocking due to teleconnection features. This can also happen if the storms have a more south-to-north axis, bringing ocean-enhanced snow bands over our area.

All in all, Alberta Clippers are normally fast moving, light winter weather events for Western Massachusetts.