TAMPA, Fla. (WFLA) — A new record has been set for the world’s longest lightning flash, according to the World Meteorological Organization (WMO) — and it’s probably far longer that you’d imagine.

A single flash covered 477 miles horizontally across the southern U.S. on April 29, 2020. The bolt of lightning stretched from south central Texas to southern Mississippi. The previous record for the longest detected megaflash was 440 miles across parts of southern Brazil on Oct. 31, 2018.

A megaflash is described as any horizontal lightning bolt that travels more than 62 miles.

The southern U.S. and southern Brazil are hotspots for lightning and megaflashes. Both bolt records were measured using the maximum great circle distance methodology, aided by satellite technology.

The WMO also released a new record for the greatest duration for a single lightning flash, which was for over 17 seconds from a thunderstorm over Uruguay and northern Argentina on June 18, 2020. The new record beat the previous record by .37 seconds, it was from northern Argentina on March 4, 2019.

The WMO Archive of Weather and Climate Extremes maintains official records of the world, hemispheric and regional extreme records associated with a number of specific types of weather. Presently, the archive lists extremes for temperature, pressure, rainfall, hail, wind and lightning as well as two specific types of storms: tornadoes and tropical cyclones.

Other previously accepted WMO lightning extremes are:

  • Direct strike: 21 people killed by a single flash of lightning as they huddled for safety in a hut in Zimbabwe in 1975.
  • Indirect strike: 469 people killed in Dronka Egypt when lightning struck a set of oil tanks, causing burning oil to flood the town in 1994