It wasn't a tornado. What was it?

CHARLOTTE, NC (WBTV) - A picture taken of one of the storms in Mecklenburg county yesterday looks particularly ominous.  It had several viewers asking, "If this wasn't a tornado, what was it?"

The lowering you're seeing is likely what is known as a wall cloud.  Thunderstorms develop when warm, moist air rises.  Eventually it cannot rise anymore, and spreads out in the upper levels.  More air rushes in to replace that spreading air, and sometimes very humid rain-cooled air is pulled into the storm.  Since it condenses more quickly than the warmer air, you will see it lower in the sky.

They are often slanted, and are often resemble tornadoes at first glance.

Sometimes, wall clouds rotate, making them look even more like twisters.  If there is significant rotation, tornadoes can develop from the wall clouds.

If you see one, regardless of whether or not it spawns a tornado, you should take that storm seriously.  A storm strong enough to produce a wall cloud will likely have strong, potentially damaging winds or large hail.

To look at other photos from Monday's storms, or to submit your own, click here.

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