Derecho is a huge shower complex that can be up to 400 km in size. This phenomenon moves across the country at a rapid pace, and can bring hurricane-like winds, heavy rains, and thunderstorms. This type of weather is more common in the interior of the United States, but discoloration of the sky is rare.
The calm before the storm
According to the National Weather Service (NWS), the sky changes color before the rains break, or sometimes during storms. According to NWS meteorologist Peter Rogers, that’s because of the way the sun hits certain particles in the atmosphere, he says. New York times.
“It must have attracted a lot of attention,” says Rogers. The green sky was most visible in and around Sioux Falls, with many residents capturing the phenomenon and posting it on social media.
According to the NWS, green may indicate that hail will fall. It didn’t happen widely, but there were showers in some places. A baseball-sized hailstone was found in neighboring Minnesota.
Derecho brought strong winds, in some places near 100 mph. Overall damage is unknown, but near Sioux Falls as the sky turned green there were no injuries. However, some buildings, trees and power cables were damaged.
The states in the middle of the United States, collectively called the Great Plains, often experience similar weather conditions. In the summer of 2020, Derecho caused massive damage. 250,000 people lost power, killing four people.