What is `Derecho` .. the storm that frightened the population and turned the sky of the United States into green

Weather of Arabia - In a strange phenomenon that frightened the residents, the sky turned in parts of the states of South Dakota, Nebraska, Minnesota and Illinois to a dark green color last week, as if it was a scene from a science fiction movie, but it is a real phenomenon that results from a storm system called “Derecho”, speaking Mostly across the central and eastern parts of the United States, but how did a storm turn the sky green?

The storm, which was accompanied by winds of about 140 kilometers per hour, cut power lines and caused some trees to fall, but what really frightened residents was the sky turning green, a phenomenon that is almost a rare occurrence, until many experienced storm chasers claimed that they did not have witnessed it before.

What is Storm Derecho? Why did you turn the traits green?

What is Storm Derecho?

The United States National Weather Service defines a derecho as "a large-scale, straight-moving, long-lived windstorm associated with a fast-moving group of severe thunderstorms, known as a medium-sized convective system".

As for the name, it has Spanish origins from the word "la derecha" which means straight, unlike a hurricane in which the winds rotate, a derecha is a storm that moves in a straight line without any rotation in its winds. These storms travel hundreds of miles and cover a vast area.

Direcho generally occurs during summer, beginning in late spring in May, and more frequent during June and July, and has also been recorded in cold weather. However, derecho is rare compared to other storm systems such as cyclones.

A storm is classified as "Derecho" if the wind speed is not less than 93 km per hour, and the impact of the wind extends more than 400 km.

On May 8, 2009 in the United States, Super Derecho was one of the "weirdest and most intense Derecho ever observed", sweeping across areas from Kansas to Kentucky with winds up to 170 km/h.

Why did the sky turn green?

Severe thunderstorms can turn the sky green due to the interaction of light with the huge amount of water it contains. Blue wavelengths, as blue light penetrates below the storm cloud, this blue color combines with the red and yellow spectrum that dominates in the afternoon sky, resulting in this union of green.