High winds last weekend in Louisville were downbursts, not tornados. What’s the difference?
Mar 21, 2026
High wings through the trees( Max Titov / Unsplash)A downburst is a weather event that can cause damage like a tornado, but it’s a unique occurrence in its own right. Learn about the differences with the latest Science Behind the Forecast.This transcript was edited for clarity and brevity.Bill B
urton: It's time for us to take a look at the Science Behind the Forecast as I'm joined by WAVE 3 meteorologist Tawana Andrew. Good morning, Tawana.Tawana Andrew: Good morning. Today's topic is very relevant, especially after the storms that we saw on Sunday night.BB: There was just a little bit of wind throughout the area on Sunday night. Those storms caused quite a bit of damage, and we're going to learn about something called downbursts today, right?TA: Yes, downbursts are one dangerous part of a thunderstorm that not everybody knows about. They are very potent winds that can plummet from a thunderstorm and then disperse once they reach the ground, because the wind, of course, cannot go straight through the ground.BB: True.TA: Physics doesn't work that way. Downburst winds can cause damage similar to a tornado, but they are an entirely separate weather phenomenon. As a thunderstorm intensifies, you have a strong updraft, so the wind going from the ground up that typically dominates the storm. This forces the cloud to grow up in altitude as raindrops and hailstones really begin to form. That updraft feeds the storm with unstable, humid air as the rain drops and the hailstones gradually get larger, and eventually they will get large enough to fall to the ground. However, if that updraft is strong enough, it will keep that rain and hail suspended within the middle and upper portions of the cumulonimbus clouds, so everything is just being held up there by some pretty strong winds.When a downburst occurs, you have that suspended core of hail and rain plunging to the ground, and it's dragging a lot of air with it. As it gets closer to the ground, it starts to gain speed because it's heavy, and of course, you have gravity.BB: That sounds terrifying!TA: It's just plummeting to the ground. You have all of that air going towards the ground. If the air below the storm is drier than the downdraft, it can pick up even more speed as the rain begins to evaporate within the dry air and cools it. It helps to accelerate that air and that core of rain and hail even more. Once the downdraft hits the ground, it's going to spread out in all directions. That means that a wide area can get impacted by a downdraft, and the winds in a downburst can gust over 100 miles per hour, so that is why we tend with downbursts to see damage similar to our tornado, but these are classified as straight line winds. The winds can be stronger than tornado winds, but they are classified as straight line winds.BB: Straight line, tornado…damage is damage.TA: It's still damage. It's still very impactful, regardless.The most common downburst is a microburst. In a microburst, the damage is spread over an area less than two and a half miles. If the damage is dispersed over a larger region then it is a macro burst, and that can go for several miles depending on how strong that downburst is.This is why it's so important to pay attention to severe thunderstorm warnings, because if the National Weather Service meteorologists detect that potential of a downburst, they will issue a severe thunderstorm warning. Now everybody always is like, let me pay attention to the tornado. No, you must pay attention to both, because both can be very impactful as they move through an area.
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