The 2017 Megaflash: The World's Longest Lightning

news image
Special Stories
15 Aug 2025 8:30 AM

Title Image Provided By: NOAA/Cooperative Institute for Research in the Atmosphere (CIRA)

The World Meteorological Organization (WMO) has recently certified a new "megaflash" as the longest in the world. The flash, which stretched from Eastern Texas to Kansas City, MO occurred in October 2017 during a mesoscale convective system. The flash covered 515 miles across a notorious stormy hot spot within the United States. A distance that would normally take eight or nine hours to drive, was covered in mere seconds.

The new record surpasses the previous from a 2020 thunderstorm across the Southern United States. So how did a lightning strike from 2017 somehow come out the blue to beat the 2020 record?

The WMO said this particular flash wasn't identified initially during the 2017 analysis, but was later discovered after re-examination of data.

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

You can learn more about other Weather and Climate Extremes through the World Meteorological Organizations Archive.

All Weather News
More
Flooding & Severe Storms Target the Southwest

Flooding & Severe Storms Target the Southwest

A low pressure system coming across the Weste

23 Oct 2026 2:05 AM
Tropical Storm Vance Forms In The Pacific

Tropical Storm Vance Forms In The Pacific

Isaias ended the late-season streak of no hur

23 Oct 2026 2:00 AM
Warmer Than Average: Above-Normal Temperatures Across the Central U.S. This Week

Warmer Than Average: Above-Normal Temperatures Across the Central U.S. This Week

WHAT TO EXPECTA ridge of high pressure will b

23 Oct 2026 1:45 AM
Josephine is Now Post-Tropical

Josephine is Now Post-Tropical

SETUPThe National Hurricane Center was watchi

23 Oct 2026 1:20 AM
Several Fires Break Out in SoCal Last Week Amid Santa Ana Wind Event

Several Fires Break Out in SoCal Last Week Amid Santa Ana Wind Event

Santa Ana winds helped several fires grow qui

19 Oct 2026 1:25 PM
Another Cold Morning Before Things Warm Back Up

Another Cold Morning Before Things Warm Back Up

Across portions of the Ohio Valley through th

19 Oct 2026 10:15 AM
Severe Risk Diminishing Saturday Morning for the Northeast

Severe Risk Diminishing Saturday Morning for the Northeast

Severe Storm PotentialSevere risk is decreasi

16 Oct 2026 10:20 AM