EAST PROVIDENCE, R.I. (WPRI) — After evaluating storm data and damage reports over the last several days, the National Weather Service (NWS) came to the conclusion that a weather phenomena known as a “derecho” occurred in Southern New England last week.
Derechos are not all that common in our part of the country. In fact, according to the NWS, the last one to impact all of Southern New England was back in July 1995.
Connecticut experienced a derecho in May 2018, however, it was not nearly as widespread.
There are two main requirements for a derecho. Strong storms or damaging winds must pass along a stretch of at least 240 miles, and there must be gusts of more than 58 mph for that entire distance.
Derechos feature straight-line winds, meaning it’s all blowing in one direction, and any trees and power lines that come down will fall in that same direction.
That’s how derechos differ from tornadoes, which feature rotation and typically leave trees and debris scattered in all directions.
Additionally, a tornado forms as part of a severe thunderstorm, whereas a derecho is a cluster or line of strong wind and thunderstorms.