Astonishing ‘Megaflash' Sets World Record for Longest Lightning Strike

Gizmodo

31-07-2025

A lightning flash tore across the sky above the Great Plains, stretching across a staggering 515 miles (829 kilometers) from eastern Texas to Kansas City. That 'megaflash' shattered the previous record for longest lightning flash of 477 miles (768 kilometers), set in 2023.
An international team of researchers documented the record-breaking flash in a new report in the Bulletin of the American Meteorological Society. Scientists were able to capture the flash thanks to advances in satellite technology and new computational tools.
The World Meteorological Organization (WMO), the meteorological agency within the United Nations, officially recognized the new record on July 31.
'We call it megaflash lightning and we're just now figuring out the mechanics of how and why it occurs,' Randy Cerveny, a professor of geography at Arizona State University and one of the authors of the report, said in a statement.
Vertically, lightning typically measures between 3.7 and 6 miles (6 and 10 kilometers), with some bolts reaching as high as 12 miles (20 kilometers). But horizontally, lightning flashes can extend much, much farther—sometimes hundreds of miles. When a lightning bolt reaches beyond 60 miles (100 kilometers), it's classified as a megaflash. Less than 1% of thunderstorms produce megaflashes, according to previous satellite observations.
Historically, scientists relied on ground-based networks of antennas to detect lightning flashes. These antennas detect radio signals emitted by lightning and use timing differences between antennas to estimate the flash's location and speed.
That changed around 2017. Since then, lightning detectors equipped to satellites have made it possible for researchers to detect and measure lightning across continental-scale distances.
The new report used data captured by the National Oceanic and Atmospheric Agency's (NOAA) GOES-16 satellite, launched in late 2016, and several other weather-monitoring satellites. These satellites use an optical sensor specialized to measure the radiant energy of light emitted during a discharge, allowing researchers to record its position and extent.
With this new satellite technology, scientists have measured hundreds of megaflashes. Since then, the record for longest megaflash has continually been broken, most recently by the 2023 flash that measured 477 miles (768 kilometers).
Some of the satellite data proved difficult to process using earlier computational methods. By applying updated, more efficient algorithms, researchers were able to reanalyze the data—ultimately identifying the new record-breaking flash.
And scientists expect megaflashes to get even more dramatic in the future. 'It is likely that even greater extremes still exist, and that we will be able to observe them as additional high-quality lightning measurements accumulate over time,' said Cerveny.