Megaflashes! New records set for longest lightning strikes, both in length and duration
Story Summary
- The new record for longest lightning strike is now 477 miles, set on April 29, 2020.
- The new record for longest-duration lightning strike is just over 17 seconds.
- “These are extraordinary records from single lightning-flash events."
The new record for the longest lightning strike is now 477 miles, set on April 29, 2020, across parts of the southern United States from Texas to Mississippi, according to the report.
And the new record for longest-duration lightning strike is just over 17 seconds, which came from a flash that developed continuously through a thunderstorm over Uruguay and northern Argentina on June 18, 2020.
“These are extraordinary records from single lightning-flash events," said Professor Randall Cerveny, rapporteur of Weather and Climate Extremes for the World Meteorological Organization (WMO), which certified the records.
World weather records can take years to officially certify.
"Environmental extremes are living measurements of the power of nature, as well as scientific progress in being able to make such assessments," Cerveny said. "It is likely that even greater extremes still exist, and that we will be able to observe them as lightning detection technology improves.”
The findings were published in the Bulletin of the American Meteorological Society.
“Lightning is a major hazard that claims many lives every year," WMO Secretary-General Professor Petteri Taalas said. "The findings highlight important public lightning safety concerns for electrified clouds where flashes can travel extremely large distances.”
The records were determined with help from lightning detection equipment onboard satellites in orbit around the Earth.
The WMO said the new record strikes occurred in hotspots for "mesoscale convective system" thunderstorms, in which extraordinary megaflashes can occur – namely, the Great Plains of North America and the La Plata basin in South America.
A megaflash is defined as a horizontal lightning discharge that reaches hundreds of miles in length.
"These extremely large and long-duration lightning events were not isolated but happened during active thunderstorms. Any time there is thunder heard it is time to reach a lightning-safe place,” lightning specialist and WMO committee member Ron Holle said.
In 2021, the U.S. saw a record low number of lightning deaths: Only 11 recorded, according to the National Lightning Safety Council.
New records were set for both the duration of a lightning strike (left, in South America) and for length of a lightning strikes (right, in the U.S.) / WORLD METEOROLOGICAL ORGANIZATION
