BRANSON, Mo. -- The rare weather event to hit the Ozarks on July 19, the night the Ride the Ducks boat sank into Table Rock Lake, was a derecho, according to a preliminary report from the National Weather Service.
This particular storm system had severe, sustained winds for more than 470 miles. By definition, a derecho is a widespread, long-lived wind storm associated with a band of rapidly moving showers or thunderstorms variously known as a squall line, bow echo, or quasi-linear convective system. Although a derecho can produce destruction similar to that of a tornado, the damage typically occurs in one direction along a relatively straight swath. As a result, the term "straight-line wind damage" sometimes is used to describe derecho damage.
Weather experts say it's a good reminder that the radar on your cell phone-- doesn't compare to listening to an expert interpret the radar.
Weather experts are getting out the word to trust the warning system because you can look at the sky and it might be bright and sunny, but what experts are seeing, compared to the lay person-- might be two very different things.
"The radar they are looking at, whether it's on the KY3 app or almost any publicly available weather app that will show radar, only shows reflectivity, and people have in their minds that if I see red, that's bad... but that's not always the case. It could just mean heavy rain. What they don't see with that radar is what the wind is doing inside of that storm, or ahead of it," said KY3 Meteorologist Brandon Beck.
He says everyone must heed the warning as soon as it goes out, regardless of what you see, or don't see in the sky.
The last derecho to hit the Ozarks was in 2009-- in Fair Grove. While they are pretty uncommon severe events-- they hit more here than in any other part of the country. We see roughly four every three years.
"Often times when the weather service issues warnings, the storms are going to be miles away... so the sun could be out-- there may not be much of an indication for a storm to come, but whether it be from a cell phone or a tornado siren, as soon as you hear of a warning from the weather service, know that that storm is going to be approaching your location," said Steve Runnels, Warning Coordination Meteorologist with the National Weather Service in Springfield, Missouri.
He says the untrained eye might not pick up on the wind associated with this type of storm-- by simply looking at radar on your cell phone. Beware, so you don't miss the danger that could come.