Winter Weather 101: Terms To Know

Winter weather can be complicated – here are some terms to know to be ready for the season.

Blizzard: A strong snowstorm with a large amount of snow and/or blowing snow, winds of 35 miles per hour or greater and visibility of a quarter-mile or less for at least 3 hours.

Nor’easter: A strong low-pressure system impacting the mid-Atlantic and Northeast. Characterized by northeasterly winds blowing in, feeding the system with warm, moist air from the Atlantic, they can cause heavy rain and snow as well as coastal flooding.

Lake-effect snow: Forms when cold, dry air moves over a lake, picking up moisture from above the surface where the water is not yet frozen. This now saturated air then brings snow to areas typically south and east of the lakes.

Snow squall: Brief yet intense snowstorms with strong winds that most often occur around the Great Lakes.

Flurries: A light snow shower for a short period of time; little to no accumulation is expected.

Sleet: Forms when snow passes through a layer of warm air and partially melts, then passes through a thick cold layer above the ground and refreezes into ice pellets. Sleet bounces on contact with the ground.

Freezing rain: Similar to sleet, it forms when snow falls through a warmer layer but it fully melts. Instead of refreezing before hitting the ground, it becomes supercooled and freezes on impact at the surface, slickening roads and accumulating on trees and power lines.

Ice storm: When a storm results in at least a quarter-inch of ice accumulating on exposed surfaces. This can cause tree branches and power lines to snap due to the weight of the ice, and roads and walkways can become hazardous due to the slippery surface.

Blowing snow: Wind-driven snow that is falling or accumulated snow that is lifted up by the wind. It can cause whiteout conditions and greatly limit visibility.

Freezing fog: When it is foggy and the temperature is at or below freezing, the water droplets in the fog can become supercooled and freeze on impact with a surface. This can cause roads to slicken and black ice could form.

Wintry mix: When two or more types of winter precipitation falls at the same time in the same place.

Snowdrift: Piles of snow that resemble sand dunes. They form from blowing snow.

Polar vortex: A large area of low pressure that surrounds the Earth's poles. It exists year-round but strengthens in the winter. However, when it weakens, it can become wavy and pockets of cold air can dip into the states, bringing a blast of arctic air that can drop temperatures dramatically.

Wind chill: Used to describe what the air temperature feels like because of a combination of cold air and wind.

Thundersnow: Lightning and thunder can occasionally form in snowstorms, typically where there is a lot of instability in the atmosphere like ahead of a warm front.

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