What is a Derecho and Could One Hit Maine?

If you have spent much time traveling to other parts of the country, you have probably realized that many weather events are regional.

For example, you'll probably never hear anyone outside of New England mention having to weather a Nor'Easter. There's also a good chance that you will never hear anyone in New England talk about graupel falling from the sky. Graupel, by the way, is kind of like hail. Think of it as snow that is the shape and consistency of Dippin' Dots ice cream.

Because so many weather phenomena are regional, there is a good chance that you have never heard about a derecho hitting Maine, New Hampshire, Massachusetts, or Vermont.

What is a Derecho?

While they are somewhat common in the midwest, a derecho is a line of thunderstorms that often include extremely high winds.

The Scijinks website describes them as:

fast-moving bands of thunderstorms with destructive winds. The winds of a derecho travel at least 58 miles per hour and have been recorded as fast as 130 miles per hour. That’s as fast as some tornados! But instead of spiraling like a tornado or hurricane, the winds of a derecho move in straight lines. That’s where the storm gets its name; the word derecho means “straight ahead” in Spanish.

The derecho 'season' in the United States runs from April through August and they are most common between May and July.

Some of these derechos are massive. They can be as much as 240 miles long. Or, wide, depending on how you look at it.

What Causes a Derecho?

According to SciJinks, derechos form because of something called a downburst. When the wet air in a thunderstorm meets with the dry air surrounding the storm, the water in the air evaporates. When water evaporates, it cools the air around it.

Since the cool air is denser, it rapidly sinks to the ground and creates strong winds called downbursts.

Do We Ever Have Derechos in New England?

While they are mostly seen in the Midwest, there are records of derecho impacting the eastern part of the United States.

The areas that are most prone to have derechos will get about three over the course of four years.

According to a map showing which parts of the United States are most likely to get a derecho, New England will see one derecho every four years.

If you are ever caught in a derecho, you should take the same precautions you would in a tornado or hurricane. Head to the basement of your building or house. If you don't have a basement, take shelter in an internal space.