Here’s what happened during the Aug. 10, 2020, derecho

This radar image shows the derecho as it approaches Cedar Rapids and other Eastern Iowa cities, shortly after noon Aug. 10, 2020. (National Weather Service)

This time-lapse matrix shows the development and movement of the Aug. 10, 2020, derecho across seven states. (National Weather Service)

As the Aug, 10, 2020, derecho barreled across seven states in 14 hours, it left nearly $13.7 million per minute of damage in its wake.

That average comes from an updated estimate of the derecho’s damage — $11.5 billion — from the National Oceanic and Atmospheric Administration, which tracks billion-dollar natural disasters in the United States.

That total makes it the most costly thunderstorm in U.S. history. Only two weather events in 2020 caused more damage — Hurricane Laura in Louisiana and the wildfires in California, Oregon and Washington state.

More than half the derecho’s damage — at least $7.5 billion, according to the state — came just in Iowa.

And nowhere in Iowa was the damage more severe than in Cedar Rapids and Linn County, where a million trees were destroyed and more than 1,000 homes declared uninhabitable.

Though most of the uprooted trees and broken branches have been removed, the absence of trees is felt, and will continue to be felt, for decades. A year later, hundreds of homes still await repairs.

» BEFORE AND AFTER: Satellite images show how the derecho changed the landscape

The devastating 2008 flood destroyed 1,300 homes and wiped out more than 1,300 jobs in Cedar Rapids, with floodwater covering 10 square miles along the Cedar River.

The equally devastating 2020 derecho damaged every block in the 75 square miles that make up Cedar Rapids, as well as neighboring Marion, Hiawatha, Robins and Ely — a 30-mile-wide swath south and north of Cedar Rapids.

Both disasters interrupted our confidence that lights will turn on and that cellphones, computers and gas pumps will work. The derecho, coming in the midst of the COVID-19 pandemic, packed an extra punch for people already struggling with life’s basic necessities. They ran out of food.

Both disasters scared and scarred us.

The storm

The derecho — pronounced duh-RAY-cho — formed the morning of Monday, Aug. 10, 2020, in northern Nebraska and southeast South Dakota, gaining strength as it raced east.

By the time it hit Des Moines, its winds exceeded 100 mph. It continued to grow in strength as it flattened corn and tore off roofs in Marshall, Tama and Benton counties, slamming into Cedar Rapids at 12:30 p.m.

Sustained, straight-line winds — 100 to 130 mph — hammered the metro area for 30 to 45 minutes. In hard-hit southwest Cedar Rapids, winds were estimated at 140 mph, the equivalent of an EF3 tornado or a major hurricane.

via GIPHY

By the time the derecho dissipated over Indiana at 7 p.m., it had crossed seven states, covering 770 miles in 14 hours, ranging in width from 20 to 50 miles.

Four people lost their lives in the storm — three in Iowa, one in Indiana.

Derechos in Iowa

Though the word “derecho” was new to many Iowans last year, other derechos have hit the state, most notably:

• May 26, 1965, in Cedar Rapids, the “worst windstorm in the city’s history,” The Gazette reported. Seventeen people were injured.

• July 28, 1986, in northwest Iowa and Des Moines.

• July 10-11, 1989, heavy damage in Tama and Benton counties, destroying 75 percent of Vinton’s trees; the derecho’s path ran from the Plains to the Mid-Atlantic states.

• July 29, 1989, from Iowa’s western to eastern border.

What made the Aug. 10, 2020, derecho different was the force and unrelenting longevity of its wind — not a tornado, but an inland hurricane — and the damage it left behind. Derechos typically last 10 to 20 minutes — not 30 to 60 as this one did.

The most damage came in Linn County, where streets in the metro area were mostly impassable and electricity was out in 98 percent of the county.

It would take days — in some cases, weeks — to reconnect people to the 21st century. It took weeks to clear the streets and 10 months to pick up the tree debris in Cedar Rapids and Marion. Hundreds of homes still need repairs, thousands of trees still need attention on private property.

To date, insurance companies have paid out $3.125 billion in derecho-related claims in Iowa. That doesn’t count the damage to the homes and cars that weren’t insured.

One year after the derecho, individuals, cities and counties are determined to continue the recovery and rebuilding. Homes are being repaired, trees are being planted, the electrical grid is being hardened.

Still, when it rains hard, and the wind blows hard, we remember.

Comments: (319) 368-7675; mary.sharp@thegazette.com