World’s longest lightning bolt stretched more than 515 MILES across US

It’s one of the most powerful natural phenomena that occurs on Earth. 

Now, scientists have recorded the longest lightning bolt in history.

The record–breaking ‘megaflash’ took place during a major thunderstorm back in October 2017. 

It extended 515 miles from eastern Texas to near Kansas City – 38 miles longer than the previous record. 

To put that into perspective, that’s about twice the length of the Grand Canyon, or the equivalent of the distance between Paris and Venice. 

If you were to cover 515 miles in a car, you’d be facing a nine-hour drive, while a flight would take at least 90 minutes, experts say.  

Researchers from the World Meteorological Organisation (WMO) hope the discovery will highlight just how far lightning can reach from its parent storm. 

‘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,’ said Celeste Saulo, WMO Secretary-General.

‘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.’

For years, lightning detection and measurement has relied on ground-based stations. 

However, satellite-borne lightning detectors in orbit since 2017 have now made it possible to continuously detect and measure lightning at continental-scale distances. 

‘The extremes of what lightning is capable of is difficult to study because it pushes the boundaries of what we can practically observe,’ said Michael J. Peterson, lead author from the Georgia Institute of Technology. 

‘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.

‘Over time as the data record continues to expand, we will be able to observe even the rarest types of extreme lightning on Earth and investigate the broad impacts of lightning on society.’

The record-breaking megaflash surpasses the previous record set by a lightning strike during an April 2020 storm, which reached 477 miles across the southern US. 

‘This new record clearly demonstrates the incredible power of the natural environment,’ said Professor Randall Cerveny, rapporteur of Weather and Climate Extremes for WMO.

‘Additionally, WMO assessment of environmental extremes such as this lightning distance record testify to the significant scientific progress in observing, documenting and evaluating such events. 

‘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.’

Most lightning flashes reach less than 10-miles long. 

However, anything longer than 60 miles is considered a ‘megaflash’. 

Megaflashes arise from long-lasting storms, which typically brew for 14 hours or more, and cover an enormous area. 

Beyond the October 2017 megaflash, several other record-breaking lightning strikes have hit the headlines over the years.

The greatest duration for a single lightning flash of 17.1 seconds was set during a thunderstorm over Uruguay and northern Argentina on 18 June 2020.

Meanwhile, the worst direct strike saw 21 people killed by a single flash of lightning in Zimbabwe in 1975. 

What’s more, a staggering 469 people were in killed by an indirect strike in Dronka, Egypt, in 1994, when lightning struck a set of oil tanks, causing burning oil to flood the town. 

The researchers hope the findings will highlight the fact that lightning is capable of travelling many hundreds of miles from the source. 

‘The only lightning-safe locations are substantial buildings that have wiring and plumbing; not structures such as at a beach or bus stop,’ said lightning specialist, Walt Lyons.

‘The second reliably safe location is inside a fully enclosed metal-topped vehicle; not dune buggies or motorcycles.

‘If lightning is within 10 km as found with reliable lightning data, go to the lightning safe building or vehicle. 

‘As these extreme cases show, lightning can arrive within seconds over a long distance, but they are embedded within larger thunderstorms, so be aware.’

WHY DOES LIGHTNING STRIKE?

Lightning occurs when strong upward drafts in the air generate static electricity in large and dense rainstorm clouds.

Parts of the cloud become positively charged and others negatively charged.

When this charge separation is large enough a violent discharge of electricity happens — also known as lightning.

Such a discharge starts with a small area of ionised air hot enough to conduct electricity.

This small area grows into a forked lightning channel that can reach several miles in length.

The channel has a negative tip that dispels charges to the ground and a positive tip that collects charges from the cloud. 

These charges passes from the positive end of the channel to the negative end another during a lightning flash, causing the charge to be released.