A clipper storm is a fast-moving, low-pressure weather system that primarily impacts North America during the winter months. These systems are known for their swift passage across broad regions, often bringing a quick burst of snow and a significant drop in temperatures. Their characteristics distinguish them from more moisture-laden storm types.
How Clipper Storms Form
Clipper storms originate in or near the Canadian province of Alberta, on the lee side of the Rocky Mountains. Their formation begins when warm, moist winds from the Pacific Ocean interact with these mountains, leading to the development of a low-pressure area. This system then entangles with the cold air masses commonly found over the Canadian prairies during winter. The powerful jet stream then steers these low-pressure systems southeastward across the continent. The air loses much of its moisture as it ascends and descends the Rockies, contributing to the dry nature of these storms.
Defining Characteristics
A defining feature of clipper storms is their rapid movement. They typically produce light, powdery snow, accumulating 1 to 3 inches due to limited moisture. These storms are accompanied by sharply colder temperatures, with drops of around 16°C possible within 10 to 12 hours after passage. Gusty winds, frequently reaching speeds of 35 to 45 miles per hour (56 to 72 km/h), are also common. The light, fluffy snow is prone to drifting.
Common Paths and Effects
Clipper storms typically track southeastward from the Canadian Prairies, moving across the Upper Midwest, Great Lakes region, and into the Northeastern United States. They travel at a rapid pace, often around 30 to 37 miles per hour (50 to 60 km/h). These systems can create slippery road conditions and reduced visibility due to light snowfall and blowing snow. When a clipper moves over the relatively warmer waters of the Great Lakes, it can pick up additional moisture, significantly enhancing snowfall through lake-effect snow. Occasionally, as they approach the East Coast, these storms can intensify by drawing in moisture from the Atlantic Ocean, potentially leading to heavier snowfall in New England.
The Origin of the Name
The term “clipper” in clipper storm refers to the swift “clipper” sailing ships of the 19th century, renowned for their speed. This name was coined by meteorologist Rheinhart Harms in the late 1960s, who observed the rapid movement of these snow-producing storms. While “Alberta Clipper” is the most common name, these systems can also be referred to as “Saskatchewan Screamers” or “Manitoba Maulers,” depending on their specific Canadian province of origin.