Q: How do blizzards form?
A: To fully understand how a blizzard is formed, we must first understand the difference between a blizzard and a snowstorm. At the core of what they are, snow falling from the sky, a snowstorm is only considered a blizzard if there are large amounts of snowfall, visibility is less than a quarter-mile, and winds are more than 35 miles per hour. These three conditions must last for at least three hours to be considered a blizzard.
So how does a blizzard form? Well, three things need to occur.
- The air temperature in the clouds and on the ground needs to be below freezing, which is 32 degrees Fahrenheit.
- There needs to be a lot of moisture or water vapor. Water vapor forms from wind moving air over a body of water. As the wind moves over the water, water is evaporated into the air, resulting in water vapor.
- Warm air needs to rise over cold air in one of two ways. First, warm air can be pulled from the equator toward the poles by the wind. Or wind can pull cold air from the poles toward the equator.
When all three of these factors occur, a blizzard forms. The cold air causes snow to form, and moisture and the warm air rising causes clouds and precipitation to form.
While blizzards are much rarer than snowstorms, their effects can be much more dangerous. Blizzards can shut down a city, ruin electrical wires, cause property damage and car accidents, and even result in death. Even though blizzards can occur anywhere that it snows, they're most common in the Plain States, the Northeast, and on mountain tops. If you live in one of these areas, it's a good idea to understand the steps to take to stay safe and warm during a blizzard.