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Name: Kelsey
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What is the relative humidity of tornados?

If there is an actual funnel cloud in the vortex, the relative humidity is 100%. The funnel dips down from the parent cloud because the pressure in the vortex is low enough to make the temperature drop below the condensation point.

However, not all tornadoes have an actual funnel cloud descending all the way to the ground, even though the vortex might be quite destructive. In those cases, the relative humidity is below 100%.

Richard Barrans
University of Wyoming

In retrospect, I think I referenced the origin of my comments incorrectly. While not "endorsing" or "promoting" any publication -- the book "STORM WARNING: The Story of a Killer Tornado" by Nancy Mathis is the sources of my response. She gives a detailed but non-technical description of tornados. Again, I am not promoting that source, but I found it useful and riveting reading.

Vince Calder

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