New megaflash lightning record exceeds distance of pilgrimage route

GENEVA (AN) — A notorious storm hotspot in the United States set a new world record for an exceptionally long lightning discharge known as a megaflash, the U.N. weather agency announced.

The longest lightning flash on record occurred in Oct. 2017, spreading for an "incredible" 829 kilometers (515 miles) from eastern Texas to near Kansas City, according to the World Meteorological Organization.

That just a bit longer than the popular Camino Francés route of the Camino de Santiago pilgrimage from France to Spain, which stretches for 790 kilometers (490 miles) and typically takes a month to hike.

It's also equivalent to the distance between Paris and Venice, WMO notes, and would take a car about eight to nine hours and a commercial plane at least 90 minutes to cover that distance.

"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,” said WMO's Secretary-General Celeste Saulo.

Lightning is a source of wonder but also a major hazard that claims thousands of lives around the world every year, according to Saulo, an Argentine meteorologist and educator, which is why it is one of the priorities of the U.N.-led Early Warnings for All (EW4All) initiative launched in 2022.

The WMO has referenced studies that conclude around 24,000 people are killed and 240,000 are injured per year by lightning globally. The EW4All initiative aims to ensure every person on Earth is protected by life-saving early warning systems for hazardous weather, water, and climate events by the end of 2027.

New uses for space-based technology

A change in technology explains the eight-year lag in certifying the extreme weather event.

Previously, lightning scientists used data collected from ground-based networks to determine the length and duration of a flash. The networks, known as a Lightning Mapping Array, are limited in how much ground they can cover.

New advances in space-based lightning mapping, however, can be used to measure the much bigger megaflashes. These make use of environmental satellites, including those in orbit from Europe and China.

Using the latest satellite technologies, a WMO committee that maintains official records on weather and climate extremes was able to recognize the new record, which was 61 kilometers (38 miles) longer than the previous record. The findings were published in the Bulletin of the American Meteorological Society.

The record-setting megaflash in the Great Plains, an area WMO recognizes as a North American hotspot for thunderstorms with extraordinary megaflashes, was one of the first storms documented by NOAA’s newest environmental satellite, but its significance was only determined later by re-examining the storm.

Among the committee's other records are a 17-second-long lightning flash over Uruguay and northern Argentina on June 18, 2020; 21 people killed in a flash of lightning that struck a hut at Zimbabwe in 1975; and 469 people killed by an indirect lightning strike on oil tanks at a flooded Egyptian town in 1994.

“The only lightning-safe locations are substantial buildings that have wiring and plumbing; not structures such as at a beach or bus stop," said committee member Walt Lyons, a past president of the American Meteorological Society. "The second reliably safe location is inside a fully enclosed metal-topped vehicle; not dune buggies or motorcycles."