The Greenfield, Iowa tornado on May 21st is still way too fresh on the minds of residents near the small Iowa town. The storm claimed five lives and injured over 30 more. And thanks to researchers and storm chasers new data is showing just how powerful and awful the storm was.

NBC News reports that a team of researchers worked to intercept the path of the storm that day after following a storm system in neighboring Nebraska. Their goal was to get close to a large tornado and measure wind speeds in and around the twister. If it sounds like a dangerous job, it is. Three storm chasers died in 2013 while chasing a powerful tornado in Oklahoma. By the time the team chased down the Greenfield tornado, they were able to set up their equipment about 300 yards from the edge of the tornado. What they recorded that day was scary and rare.

The Greenfield tornado proved to be a rare storm for several reasons. NBC News reports that data showed:

  • Wind speeds inside the tornado reached over 300 mph, only the third tornado ever recorded with wind speeds that high.
  • The tornado moved at an alarming rate of 55 mph, nearly twice the normal speed of a tornado.

The tornado also displayed multiple vortices within the storm. NBC News reports that the chasers hope that the data from the Greenfield tornado can help researchers understand how wind speeds aloft can affect damage on the ground. It could also help develop better tornado prediction systems and stronger structures to withstand the storm.

KEEP READING: What to do after a tornado strikes

LOOK: The most expensive weather and climate disasters in recent decades

Stacker ranked the most expensive climate disasters by the billions since 1980 by the total cost of all damages, adjusted for inflation, based on 2021 data from the National Oceanic and Atmospheric Administration (NOAA). The list starts with Hurricane Sally, which caused $7.3 billion in damages in 2020, and ends with a devastating 2005 hurricane that caused $170 billion in damage and killed at least 1,833 people. Keep reading to discover the 50 of the most expensive climate disasters in recent decades in the U.S.

Gallery Credit: KATELYN LEBOFF

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