This transcript was edited for clarity and length. It originally aired November 2021.
Bill Burton: It's time for us to take a look at the Science Behind the Forecast as I am joined by WAVE 3 meteorologist Tawana Andrew. Good morning, Tawana.
Tawana Andrew: Good morning. Today, we're going to be myth-busters.
BB: Myth-busters! I like it. Let's bring on some myths to bust. What exactly are we busting this time around?
TA: There's a huge misconception that rivers can disturb large storm systems and thunderstorms and even keep tornadoes from forming in certain areas. That is not true.
BB: OK, we're going to bust that myth.
TA: A cumulonimbus cloud, the thunderstorm cloud, can climb up to 40,000 to 60,000 feet into the atmosphere. That's about seven and a half to 11 miles. Thunderstorms are rarely affected by small features on the Earth's surface, like rivers. There's data that shows that even the Mississippi River, one of the largest of course, in our country, doesn't affect thunderstorms. When you look at the Amazon River, it is much larger than the Mississippi, so that's a different situation. But in the U.S., you don't really see rivers affecting thunderstorms like that.
Now you have bigger bodies of water, let's say, like the Great Lakes, they're more likely to impact the weather system. For example, Lake Ontario is around 7,000 square miles, and Lake Superior is about 31,000 square miles at its widest point. The Ohio River is a mile wide, so it's really not having that much of an impact on anything.
The second myth that we want to debunk today is the belief that rivers can protect a region from a tornado. That is also not true. I've heard a lot of people tell me this, like, “Oh, Louisville is fine, because tornadoes won't cross over the river.” That is definitely not true. Tornadoes, in general, typically have an intermittent path, so they'll go up, they'll come down. That's entirely normal. And there's plenty of data to show tornadoes crossing over rivers. A really interesting example of this is in 1925. It's what's called the Great tri-state tornado. It traveled from southeastern Missouri into Indiana, killing about 695 people along the way. This tornado crossed two rivers. It crossed the Mississippi and it crossed the Wabash. That just shows you that these tornadoes, even an incredible strength, can easily cross rivers.
Then there's one in our area that I think a lot of people actually know about, but don't realize that they know about it. The March 2, 2012 tornado. The one that destroyed portions of Henryville. That actually started in Washington County, Indiana, went all the way through Henryville in Jefferson County, Indiana. Then it crossed the Ohio into Trimble County, Kentucky, and they caused even more damage there. You can even Google the pictures and the video of it crossing the river, which is absolutely mesmerizing to watch.
It's also important to remember that we have water spouts. Those are just tornadoes over bodies of water, and they can be just as dangerous as a regular tornado. So those are some of the myths that I hear all the time, especially when it's severe weather season. Fall is basically our second severe weather season. It's just a reminder, maybe don't believe everything you read on the internet.
BB: The only thing you should believe is Science Behind the Forecast, and now we have a much better understanding of why it's a myth that a river has an effect on a tornado, that it might stop a tornado, it doesn't. That myth has been busted thanks to Science Behind the Forecast with WAVE 3 meteorologist Tawana Andrew. Thanks for the knowledge, Tawana.
TA: Of course.
