Longest lightning flash on record stretched 515 miles across US

Hear from a storm photographer on his close encounter with a bolt of lightning in the Lone Star State.

The World Meteorological Organization says there is a new record-holder when it comes to lightning bolts seen from space – an extraordinary 515-mile streak which illuminated the skies from eastern Texas through Missouri in October 2017.

The record-breaking “megaflash” occurred during a thunderstorm system known as a Mesoscale Convective System, which was moving along the Gulf Coast ahead of a frontal boundary.

Members of the WMO said they were able to identify the bolt using satellite-based mapping technology and submitted their findings to the Bulletin of the American Meteorological Society.

“This new record clearly demonstrates the incredible power of the natural environment,” Randall Cerveny, a member of the WMO, stated. “It also testifies to the significant scientific progress in observing and evaluating such extreme events.”

The World Meteorological Organization says a lightning bolt that was visible for some 515 miles from eastern Texas through Missouri in October 2017 is now considered to be the world’s longest.

(NOAA/World Meteorological Organization / FOX Weather)

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Recent advances in space-based lightning mapping technology are said to aid in the ability to measure flashes more accurately.

“The extremes of what lightning is capable of is difficult to study because it pushes the boundaries of what we can practically observe,” Michael Peterson, lead author and committee member of the Severe Storms Research Center, said in a statement. “Adding continuous measurements from geostationary orbit was a major advance. We are now at a point where most of the global megaflash hotspots are covered by a geostationary satellite, and data processing techniques have improved to properly represent flashes in the vast quantity of observational data at all scales.”

The flash replaces the previous record holder, which occurred in April 2020, when a bolt’s flash was estimated to have been more than 477 miles long and stretched from Texas through Mississippi.

Vaisala, a global technology company, detected some 242,101,157 lightning bolts in the skies over the U.S. in 2024, with an annual average of more than 20 million that actually reach the ground.

209,484,916 in-cloud and cloud-to-ground lightning events were reported in the United States in 2024.

(Vaisala / FOX Weather)

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In addition to records relating to the length of the flash, the WMO also highlighted other historical incidents involving acts of Mother Nature.

The longest-duration flash on record lasted more than 17 seconds over parts of Uruguay and northern Argentina in June 2020.

Other notable lightning-related incidents include a 1975 strike that killed 21 people in Zimbabwe and a 1994 incident in Egypt that killed 469 due to a lightning-induced oil tank fire.

The organization emphasized that while lightning remains a source of awe, it is also a considerable public safety hazard.

“Lightning claims many lives each year and can spark wildfires or pose hazards to aviation,” WMO Secretary-General Celeste Saulo stated. “Understanding the scale and behavior of extreme flashes is vital for public safety and risk management.”

Chris Vagasky, Meteorologist and Lightning Applications Manager for Vaisala, joined FOX Weather to talk more about lightning for Lightning Safety Awareness Week.