A lightning strike that lit up the sky across three US states has been confirmed as the longest on record, with the World Meteorological Organization (WMO) today certifying the 768-km (477-mile) length of the flash that occurred back in April 2020. The event smashes the previous length record for a lightning strike, and is accompanied by another newly confirmed record for a longest duration single-flash event.
The record-setting lightning strike stretched across the night sky from Texas, over Louisiana and into Mississippi, and is a good 60 km (37 miles) longer than the previous record. That 709-km (440-miles) strike occurred in southern Brazil in October of 2018 and was recorded using the same maximum great circle methodology, which accounts for the curvature of the Earth.
These measurements made use of recent advances in the way scientists map lightning strikes, which historically relied on ground-based networks of antennas, GPS receivers and processing systems called Lightning Mapping Arrays (LMAs). These, however, have had limitations in terms of the scale of lightning that can be observed, but recently satellite technology has allowed them to take these measurements into new terrain.
This includes data from NASA's Geostationary Operational Environmental Satellites, along with Europe's Meteosat Third Generation satellite and China's FY-4 Lightning Mapping Imager. These enable scientists to map the flash extent and duration of lightning over wider geospatial regions, and are expected to provide close to global coverage of lightning events moving forward.
"Lightning is a surprisingly elusive and complex natural phenomenon for the impact that it has on our daily lives," said lead author of the paper describing the research, Michael J. Peterson from Los Alamos National Laboratory. "We are now at a place where we have excellent measurements of its many facets, which allow us to discover surprising new aspects of its behavior. Now that we have a robust record of these monster flashes, we can begin to understand how they occur and appreciate the disproportionate impact that they have."
Alongside the longest strike ever recorded, the research also details the longest duration for a single flash of lightning, at 17.1 seconds, which took place amid a thunderstorm over Uruguay and Argentina in June of 2020. This takes the mantle from a previous flash of 16.73 seconds that occurred in the same region, over northern Argentina, in 2019.
“These are extraordinary records from single lightning flash events," said Professor Randall Cerveny, rapporteur of Weather and Climate Extremes for WMO. "Environmental extremes are living measurements of the power of nature, as well as scientific progress in being able to make such assessments. It is likely that even greater extremes still exist, and that we will be able to observe them as lightning detection technology improves."
The study was published in the Bulletin of the American Meteorological Society, while the video below offers an overview of the research.
