The World Meteorological Organization (WMO) confirmed on July 31 that a “megaflash” lightning bolt spanning 829 kilometers—observed over the United States—has set a new world record for the longest single lightning discharge. This surpasses the previous record by 61 km.
⚡ Record-Breaking Details
- Date/Time: October 22, 2017, lasting over 7 seconds
- Path: From eastern Texas to near Kansas City, Missouri, crossing five U.S. states
- Equivalent Distance: Paris, France → Venice, Italy (≈9-hour drive / 90-min flight)
The record was certified by the WMO’s Weather and Climate Extremes Committee.
📜 Historical Context
The prior record (768 km) was set by an April 29, 2020, lightning flash across Mississippi, Louisiana, and Texas. Both measurements carry a ±8 km margin of error.
🛰️ Why an “Old” Flash Broke the Record Now?
- Past Limitations: Ground-based “Lightning Mapping Array” networks struggled to detect massive-scale discharges.
- Satellite Revolution: Advanced geostationary satellites (e.g., GOES-16/17) now enable tracking of lightning across continents.
- Rediscovery: Re-analysis of 2017 storm data using new tech revealed this previously overlooked megaflash.
💬 Expert Insights
- Randall Cerveny (WMO Rapporteur):“Lightning can travel far beyond parent thunderstorms—explaining why people report ‘bolts from the blue’ in clear skies.”
- Michael J. Peterson (Atmospheric Scientist):“Satellite imaging lets us detect previously invisible extremes. As data expands, we’ll identify Earth’s rarest megaflashes and assess their societal impacts.”
⚠️ Public Safety Warning
WMO Secretary-General Celeste Saulo emphasized:
“While lightning inspires awe, it kills thousands annually. This discovery highlights critical risks to aviation, wildfire ignition, and public safety from charged cloud systems capable of producing megaflashes.”