Landspouts and snakes

Wait, snakes? Yeah, I'll get to that at the end of this blog post... but first, a based on yesterday's post, a lesson on landspouts.

Yesterday afternoon, a little cell in Iowa had a tornado warning on it. Based on radar, it looked like it would be doing little more than producing a small shower, but there were numerous reports of a funnel and even a tornado - including one from a pilot landing at the Fort Dodge airport. As you can imagine, this tornado wasn't the same type that we typically see in those monstrous supercells. In fact, it looks to me that this tornado is actually what we call a landspout.

The first thing you probably think of when you read "landspout" is something that's much more well known: the waterspout. They don't form in the same way, but they look the same. While we typically think of tornadoes as being a big, dark, wedge-shaped cloud... a landspout looks like it has smooth edges, just like a waterspout.

Supercell tornadoes form because there is a tighter region of rotation within the thunderstorm. That ends up becoming a wall cloud, which then produces a funnel and tornado. Landspouts develop because of some sort of horizontal spin near the ground that gets pulled up into the storm base. As that happens, it condenses and the funnel becomes readily visible. The vortex is usually pretty narrow. Under normal circumstances, they're also rather weak, but that doesn't mean they're not dangerous or can cause damage.

With yesterday's landspout, there is mayyyyybe a very tiny wall cloud coming out of the storm's base, but it's a little questionable whether it's actually one or not. Also notice how short the storm is! The height of the base makes up a pretty big chunk of the height of the storm itself. In supercells, the top of the storm can be 50,000 feet high while the base of the storm is 1,500 feet off the ground. Definitely not that huge of a difference in this particular storm.

I also posed the question about what the outflow from the thunderstorm does to the landspout. Here are two pictures that illustrate it wonderfully...

When rain comes out of the cloud, it drags cooler air down with it, and that air has to go somewhere when it hits the ground. It spreads outward, of course, and you can clearly see the effect of that outflow on the landspout in these pictures. The second picture is pretty remarkable at how intact the vortex is, despite getting pushed way outward - so much that it's pretty much horizontal! However, it can't get stretched out much more than that before the spinning motion at the ground is totally cut off from the storm's updraft, as seen in the pictures that WI Wx Buff linked to in the comments section of yesterday's post.

(Note... all these pictures are from KCCI viewers and are hosted by the Iowa Environmental Mesonet.)

I think I've answered the questions regarding landspouts, but if any more pop up, just leave something in the comments section. Actually, speaking of leaving comments... what do you all think of a "weather whys" every week either on the weather page or here on the blog? Any weather question would be fair game and I'd pick out a question to answer each week. Let me know your thoughts!

And finally... the snake part of this post. If you caught the 10pm newscast last night, we showed a clip at the end of the show about a meteorologist in Iowa who had a snake on him at the Iowa State Fair. Well... we didn't show you the whole thing. The video and audio become absolutely hilarious. The meteorologist in question is Kurtis Gertz (same pronunciation, similar spelling, no relation!), one of the great people I interned under when I was in college. Kurtis, as anybody who knows him would expect, took the sequence of events all in stride. Definitely a memorable couple of minutes in his career! That said, don't expect to see a giant snake on my shoulders (or *ahem* anywhere else) anytime soon.