Derecho winds cause problems in the Midwest

Last week, very strong winds moved through the central portions of the country, knocking out power and causing some widespread damage.

These strong winds were classified as a “derecho.” Known as a widespread and long-lived wind storm, derechos are associated with a fast-moving group of heavy thunderstorms. According to the Storm Prediction Center, to be classified as a derecho, winds are at least 58 miles per hour with occasional gusts topping 75 miles per hour, and the damage often occurs in one direction along a straight path of at least 250 miles.

The destruction associated with a derecho is similar to a tornado. The event usually produces hurricane-force winds, heavy rainfall and flash flooding. Officially, a tornado is a rotating column of air that comes in contact with the ground.

Derechos are rare events, but in 2020, there have been five occurrences in the U.S. The first one this year happened April 28-29 in parts of the central and southern Great Plains. The storm produced more than 450 reports of severe weather from Illinois southward into Texas and Louisiana. The derecho traveled more than 500 miles before moving off into the Gulf Coast. Winds gusts were near 80 miles per hour and hail of nearly 4 inches was reported.

The same area reported another derecho on May 3. On June 3, the third derecho hit Pennsylvania and New Jersey with a wind gust of 89 miles per hour that left more than 700,000 people without power.

An unusual derecho moved across the Rocky Mountains toward the High Plains on June 6-7. The storm originated west of the Continental Divide, which is extremely rare. In fact, that was the farthest to the west a derecho has formed in history. There was a 110-mile wind gust at the Winter Park Ski Resort in Colorado.

Parts of western Colorado had wind gusts of an amazing 120 miles per hour. That’s as strong as a Category 3 major hurricane.

The most recent derecho occurred in the Midwest on June 10. According to various news sources, a powerful line of thunderstorms stretched for more than 400 miles from central Michigan to eastern Kentucky. Wind gusts in some areas were over 80 miles per hour. Nearly 700,000 people in the Midwest, mostly in Michigan, were left without power.

Data from Wikipedia indicates that counting the five derechos in 2020, there have been a total of 35 reported derechos since 2010. In 2018, there were seven big derecho storms, with two in 2019. At this rate, we could see a record number of derechos this year. Most of these big storms occur in the spring and summer months, mostly May, June and July. However, there have been reports of these massive storms as late as October. In 2010, severe storms that likely included derechos were reported on Oct. 23-28, the latest in recorded weather history.

The majority of derechos form in the U.S. east of the Rockies. There have been occasions of these storms forming in Europe. The last occurred from Aug. 10-12, 2017, from east Czechia through Poland. An extremely rare derecho developed over Finland on July 29-30, 2010.

Derechos are very rare in other parts of the world. In South America, there was a huge derecho that downed more than 540 million trees in the Amazon Rainforest in Brazil from Jan. 16-18, 2005.

Due to the mountainous terrain, there have not been any derechos reported around North Idaho. However, many will never forget a system of historic proportions slamming into the northwestern portion of the country on Nov. 16, 2015. Very strong winds led to numerous power outages, downed trees and power lines and damaged buildings. More than 1 million people were left without power across the Northwest.

On that November day, winds were gusting to 60 miles per hour at Cliff’s station on Player Drive. The highest wind gust at the Coeur d’Alene Airport was 58 miles per hour. The highest wind speed reported in Idaho was in Bonner County at Colburn with a whopping 101-mile per hour gust. The strongest wind gust in eastern Washington last November occurred at the Mission Ridge Ski Area in Chelan County with an incredible gust of 137 miles per hour.

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In terms of our local weather, temperatures will warm up later this week, but last Tuesday, June 9, a record low maximum temperature of 52 degrees was reported at Cliff’s station. Our wet weather pattern from May has carried over into this month as we may be close to the June normal of 1.93 inches.

Remember, with these weather extremes, we often go from cool and wet on one side to very warm and dry on the other. Therefore, Cliff and I believe that conditions will start turning drier and much warmer by late this month and into July.

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Contact Randy Mann at randy@longrangeweather.com