So What is a Microburst?

This damage yesterday out in the Steadman Community (Batesburg-Leesville), was caused by a Microburst, with gusts to 70 mph.

Pict4 Pict3 Pict2

So what is a Microburst?

You’ve probably hear the term Microburst, Downburst, or Macroburst. The are all different sizes (Micro-small, Down-medium, Macro-big) of the same phenomenon. Here’s how it works. Just as warm air rises, cold air sinks. When the cold air from a thunderstorm hits the ground it spreads out very quickly along the ground. Think of squirting a hose on the sidewalk in the summer – the water spreads out very quickly once it hits the ground. Winds can gust to more than 150 mph in the most intense Microbursts.

Capture

Below is a side view of a Microburst. If you click on it, you’ll see it animate.

Downburst Animated Gif

Any of these “bursts” (Micro, Macro, or Down) can cause significant damage – in many cases just as much as tornadoes. Here in the Midlands we get more damage annually from these different “bursts” than we do from tornadoes. And it’s important to remember that all of these “bursts” come from thunderstorms. So when we warn you of the threat of strong to severe storms, it’s worth a listen.

A little history on all this. You’ve probably heard of the Fujita Scale. It’s the scale that ranks tornadoes from 0 to 5. This scale is named after one of the great research meteorologists, Dr. T. Theodore Fujita. He spent his career researching tornadoes. His research not only significantly enhanced our understanding of tornadoes, but he also discovered something that we previously didn’t know anything about – what he termed Downbursts, Macrobursts, and Microbursts. His input was critical in unraveling the mystery of these different “bursts” and the havoc they can wreak. On June 24, 1975 an Eastern Airlines plane crashed while attempting a landing at JFK. It killed 112 people and injured 12. Fujita was brought in to analyze what happened. He observed that it was a Microburst that caused the plane to crash. Because of his work, radars were designed to identify these “bursts” and these radars are now installed at airports. So we now have the tools to avoid flying into any of these “bursts” and consequently our air travel is much safer. If you’d like to read the full report on how Dr. Fujita discovered Downbursts, Macrobursts, and Microbursts, here’s a link to a great article. https://www.researchgate.net/publication/252272974_The_Discovery_of_the_Downburst_T_T_Fujita’s_Contribution

 

 

Categories: Weather Blog