Understanding Lightning

By John S. Jensenius, Jr., NWS Lightning Safety Specialist

Lightning is one of the top three storm-related killers in the United States. It is also one of the least understood weather phenomena. The Overview Section gives a brief introduction to lightning science and safety. Want to learn more? In the Understanding Lightning Section, you can find a more detailed look at the science behind one of nature's most underrated killers.

• Introduction
• Thunderstorm Development
• Thunderstorm Electrification
• Types of Flashes
• Initiation of Leaders
• Negatively-Charged Flash:
  • Initiation of Stepped Leader
  • Making A Connection With The Ground
  • Return Stroke
  • Subsequent Dart Leaders and Return Strokes
  • Slow Motion Video Of Lightning Flashes
  • Ground Current
• Positive Flash
• Upward Leaders/Discharges
• Continuing Current/Hot Lightning
• Thunder
• Acknowledgements And References