Bogus Tornado, But How To Tell?

The tornado sirens in Columbus, Georgia blared Wednesday afternoon, but there was no tornado (see article). What happened?

A sheriff's deputy saw some low-hanging clouds that he believed were a funnel cloud, and sounded the alarm. Better safe than sorry, he said.

And he shouldn't feel bad, according to AccuWeather.com RadarPlus, strong thunderstorms were moving through the area at the time (see radar animation, I also looked at the Base and Storm-Relative velocity shots but didn't see any radar indication of rotation), and no Severe Thunderstorm Warnings or storm reports were issued to the government that day, so his report was probably incorrect.

But even this guy did not make the mistake that amateurs sometimes do, of identifying low-hanging clouds as funnel clouds when the weather conditions are not even ripe for storms. I.e. if it's cold outside, it's extremely unlikely that you're looking at a tornado.

The truth is, it's sometimes hard to tell whether evil-looking clouds are tornadoes.

Take this photo that I took in 1995 in North Carolina, for example:

It's not a tornado! But it sure looks suspicious. I'm still not sure what it was, just a weird cloud formation I guess. I've seen other similar photos of "columns of air", I think there's a term for it but it escapes me. If you know what I'm talking about, email me. To see great example photos showing things that look like tornadoes during severe thunderstorms, but aren't, click here for photos from Roger Edwards, storm chaser extraordinaire, king of the Tornado FAQ, and a blogger himself.

So how do you know? Rotation is the key. If you're close enough to see rotation but nothing's moving, then it's not a funnel cloud or tornado. Believe me, you'll know if you see rotation. I wasn't sure until I saw my first funnel cloud up close at Long Beach, North Carolina, on the outer edge of Hurricane Alex in 2004 (see photo below).

The photo itself isn't too impressive, but trust me, that baby was spinning rapidly and there was no question what it was. I was lucky enough to have my camera, but not my video camera. I took photos of various other cloud protrusions shortly after the funnel dissipated, but I saw no rotation, so there were no additional funnel clouds.

There are other times when it's less obvious -- take this photo for example which I snapped at the same beach a year later. Visibility was bad and the funnel was pretty far away, so the photo's not great. But here's the story -- I could tell by the smooth rope-like appearance that this was a funnel cloud or tornado (or probably water spout as it was probably over the sound), even though I wasn't close enough to confirm rotation. Sidenote: I really wanted to go in for a closer look but we were packing up to drive back home and my wife nixed that idea. I said "Honey, if I can't drive, then you are, while I call in my Skywarn report."