Unlike Tornado Alley, which is generally flat and open, Dixie Alley has more hills and trees making it harder to spot tornadoes. Plus, there's a higher occurrence of rain-wrapped tornadoes, which are more difficult to detect via radar. Waxler and Elbing hope a future infrasonic warning system could help overcome Dixie Alley's tornado tracking challenges and give the region's residents more warning. But there's still a key mystery that researchers have yet to solve before they can say with full certainty that a system like this would work: They don't know what exactly in a tornado emits the infrasonic signature.
What's more, Waxler said some skeptical members of the meteorological community have suggested there's something else making those infrasonic sounds, which is why he and other researchers are trying to eliminate other possible sources, like thunder. They're also looking at storms that didn't produce tornadoes to make sure those didn't also emit signatures. Elbing talked about solving other riddles, as well, like the direction of wind patterns, which can affect how and where sounds are picked up.
And, you can't exactly replicate any of this research in a lab. Down the line, he envisions having lots of arrays and better tools for modeling factors like wind direction, but that aid hasn't arrived yet. Assuming all that gets sorted, there's the technological challenge of how to one day quickly get the data, process it and send it to the Weather Service when a tornado is actually occurring so that it's helpful in issuing early warnings.
How the rest of the work on this technology plays out depends somewhat on funding. He's optimistic that there's increased interest, particularly because of the Southeast's vulnerability.
Waxler thinks that if the money holds out, the Weather Service could be able to use the technology to augment radar within the next few years, and that it could cover threatened areas with lines of arrays 40 km apart along lines of latitude. For those who "live in troubled regions," as Adrienne Rich put it in her poem Storm Warnings, they'll need to rely on the tried and true warning systems until the sound technology can be perfected.
That includes television weather reports -- sometimes epic broadcasting marathons of rolled up sleeves and meteorologists passing through the background of the shot, brows furrowed. Then there are tornado sirens -- Nashville put up its first in and now has sirens across the city -- and the FCC-run Weather Emergency Alerts system pushes warnings directly to your phone.
Other times, texts and calls from friends and family might be the red flag. Now of course, there's social media. But for anyone in forecasting, a pressing thought is how to effectively reach people, particularly if severe weather is supposed to hit at night. For the Johnsons, it was a marked shift in tone from NashSevereWx , a local account co-run by citizen weather tweeter David Drobny, that finally drove them to their basement with a few minutes to spare.
While the account is often lighthearted, even suggesting when an extra swipe of deodorant might be necessary in hot weather, it was an all caps plea to seek shelter that drove them out of their room, where the batting cage plowed into the roof.
Drobny tells me that he and the others who work on the account always remember that "underneath the radar are real people. One hundred and eight days after that batting cage smashed into their house, the Johnsons finally got a new roof back. The coronavirus pandemic has slowed reconstruction and a derecho storm , with 60 to 80 mile per hour winds in May, damaged their house further. As of July, they've had their sunroom reframed and the master bedroom replaced.
Work is slow but moving, finally. They still think about that March night when they ended up right in the path of the storm, their ears popping from the pressure change, and not knowing just how long the tornado was on the ground for before they even knew.
Getty Images. Erin Carson Nov. What is a tornado? A tornado is a narrow, violently rotating column of air that extends from the base of a thunderstorm to the ground.
Where do tornadoes occur? Tornadoes can occur whenever and wherever conditions are right! Tornadoes can occur in every state in the United States, on any day of the year, and at any hour. Where is Tornado Alley? Tornado Alley is a nickname for an area that has more tornadoes than other parts of the U.
You may receive a warning via your favorite weather app, such as The Weather Channel or Weather Underground , a Wireless Emergency Alert , over the radio or from local television.
If you only hear the warning, you will know that your part of a county or city is in a warning and that you should take shelter immediately. You're probably used to seeing the graphical depiction of a warning as a polygon either on a website or on television. If your location is in that polygon, take shelter. If not, it's not a threat, at least not yet. This paradigm of warnings, together with dual-polarization Doppler radar, severe storm research and a more dense network of spotters, has led to an average lead time of 13 minutes for tornado warnings.
We've written before about the false-alarm challenge with tornado warnings , due to the limitations of Doppler radar detecting rotation near the ground, among other reasons. Let's put the detection problem aside and consider the case of a confirmed tornado and its accompanying tornado warning as it's issued now.
In the example tornado warning below, the thunderstorm responsible for the tornado is at the lower left part of the red polygon at the time the warning was issued, near the town of Reasnor. Assuming this tornado had just developed, prompting this warning, the towns of Newburg, Grinnell and Ewart at the far edge of the warned area get a lot of warning lead time.
That's not the case for the town of Reasnor. The vast Plains has a long history of extreme weather. Even with the inclusion of the Dallas metro area in the map above, the population density across the region is just 29 people per square mile.
The people of this land have a longstanding tradition of depending on the weather for their livelihood. Despite the harsh reality of drought and severe weather, the region has the highest percentage of land farmed in the United States, and remains a critical supplier of food for the plus million people living in the U. Of the 58, tornadoes on record in that period, 16, of those occurred in Tornado Alley, which is a long-term average of tornadoes per year.
This scale ranks tornadoes by estimated wind strength , with EF0 gusts of 65 to 85 miles per hour being the weakest, and EF5 winds over miles per hour being the strongest. There are 59 confirmed F5 or EF5 tornadoes on record, and 37 percent 22 of those have occurred in Tornado Alley. In fact, for each strength category the distribution is about the same. Those within Tornado Alley account for about 35 percent.
The exception is EF0 tornadoes, with 51 percent of those occurring in Tornado Alley.
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