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Megaflash Lightning Strike in 2017 Was the World’s Largest, Covering 515 Miles

This incredible lightning strike traveled a distance of 515 miles in 8 seconds.

By Moss & FogUpdated 2 min read
A lightning bolt captured in a long-exposure photograph, its branching discharge spreading across a dark sky, a contained version of the 2017 megaflash event, which traveled 515 miles across the southern United States and held the record as the world’s longest single lightning strike ever documented

In 2017, a single lightning bolt zipped across the skies of Texas, Louisiana, and Mississippi, spanning a staggering 515 miles (828 kilometers) in one unbroken flash. That’s the equivalent of Paris, France to Venice, Italy.

A dramatic lightning bolt illuminates a dark sky, showcasing multiple branches of electric light against purple storm clouds.
Photo by Felix Mittermeier on Unsplash

Known as a megaflash, this record-breaking bolt lasted over 8 seconds, traveling sideways through storm clouds like an electric river in the sky.

A visual representation of a megaflash lightning bolt spanning across storm clouds over a landscape, showcasing intricate blue lightning patterns.
A visualization of a megaflash that extended 515 miles created from data provided by NASA and NOAA. Michael Peterson / GTRI

Verified by the World Meteorological Organization, it remains the longest lightning strike ever recorded on Earth.

Composite satellite imagery of the mega flash. Michael Peterson / GTRI

“Lightning is a source of wonder but also a major hazard that claims many lives around the world every year and is therefore one of the priorities for the international Early Warnings for All initiative.

These new findings highlight important public safety concerns about electrified clouds which can produce flashes which travel extremely large distances and have a major impact on the aviation sector and can spark wildfires,”

-WMO Secretary-General Celeste Saulo

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This storm-prone area of the United States is used to large thunderstorms, though strikes of this magnitude are rare. These enormous strikes happen at heights of 10,000 to 18,000 feet above the ground, in the middle or upper layers of the thunderstorm.

A digital illustration of the megaflash lightning bolt spanning across storm clouds, illustrating its complex, jagged path of electric discharge in the skies over Texas, Louisiana, and Mississippi.
GTRI Senior Research Scientist Michael Peterson
A lightning bolt captured in a long-exposure photograph, its branching discharge spreading across a dark sky, a contained version of the 2017 megaflash event, which traveled 515 miles across the southern United States and held the record as the world’s longest single lightning strike ever documented
Photo by Micah Tindell on Unsplash

For more stories on lightning, check out this Moss and Fog article about Lake Maracaibo in Venezuela, that gets thunderstorms 250 days a year.

By Moss & Fog Staff

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