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Thunder is produced by lightning rapidly heating and expanding surrounding air.

The Claim

Thunder is produced by clouds colliding with each other.

Verified by Lenz ·

The Short Version

Thunder is caused by lightning, not by clouds colliding. A lightning discharge rapidly heats the surrounding air, making it expand explosively and generate the shock wave heard as thunder. Major meteorological and scientific sources consistently describe this mechanism and provide no support for cloud collision as the cause.

Caveats

  • Cloud-to-cloud lightning describes an electrical discharge location, not a collision between clouds.
  • Charge separation within storm clouds is part of lightning formation, not the direct sound-producing mechanism.
  • The claim replaces the established mechanism with one unsupported by the cited scientific sources.

The Receipts

  1. What Causes Lightning and Thunder? | NESDIS

    nesdis.noaa.gov

  2. Understanding Lightning Science

    weather.gov

  3. Lightning

    weather.gov

  4. ACP - On the impact of thunder on cloud ice crystals and droplets

    acp.copernicus.org

  5. Severe Weather 101: Lightning FAQ

    nssl.noaa.gov

  6. The Sound of Thunder | National Oceanic and Atmospheric Administration

    noaa.gov

  7. What causes the sound of thunder?

    loc.gov

  8. Thunderstorms

    repository.library.noaa.gov

  9. Explainer: what is thunder? - Social Media Blog - Bureau of Meteorology

    media.bom.gov.au

  10. What causes the sound of thunder? | Library of Congress

    loc.gov

+ 20 more sources — see the full list on Lenz

Filed Under

CloudsThunder

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