Longest lightning bolt on record stretched for 709km

A lightning flash that stretched from Argentina across Brazil all the way to the Atlantic Ocean is the longest in recorded history.

The 709km lightning bolt would be long enough to stretch from Sydney to Melbourne.

Using new satellite lightning imagery technology, the World Meteorological Organisation (WMO) declared the lightning bolt a world record holder.

It was recorded during a storm on October 31, 2018.

The WMO also announced a new record for the lightning flash with the greatest duration.

That flash stretched for 16.73 seconds during a storm in northern Argentina on March 4, 2019.

WMO chief rapporteur Randall Cerveny said the records were "extraordinary".

"Environmental extremes are living measurements of what nature is capable, as well as scientific progress in being able to make such assessments," Professor Cerveny said.

"It is likely that even greater extremes still exist, and that we will be able to observe them as lightning detection technology improves."

The previous record for the longest lightning flash was in 2007 in the US state of Oklahoma.

It was only half the size of the new record holder, stretching 321km.

The longest-lasting lightning flash had previously been recorded as 7.74 seconds, taking place over Provence-Alpes-Cote d'Azur in France in 2012.

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