Keep your eyes and ears open for unusual weather

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Eureka Springs now has weather-warning sirens, and they went off three times April 30. But what do they mean?

Eureka Springs Fire Chief Nick Samac, who is also Emergency Management Coordinator for Carroll County, said the sirens are tested at noon every third Tuesday of the month. When the sirens sound at times other than that, it is a warning for people to be alert to the potential of bad weather such as tornadoes or hail storms, and to take cover.

“Generally, they get their indicators to sound that alarm when a tornado watch has been issued out of the National Weather Service in Tulsa,” Samac said. “Depending on the severity of what is coming our way, there is a possibility the siren will sound again if impending storms are still a threat.”

A common complaint from people is that they don’t hear the sirens if they are inside. But Samac said the sirens are meant for people who are outside to be warned to take shelter inside.

“Inform yourself,” Samac said. “There are apps on your phone you can download. You can watch live radar on your phone or computer. Plan and prepare in advance what you are going to do when these kinds of things are going to happen.”

Carroll County doesn’t have any FEMA-approved tornado shelters. Samac said not many counties in the entire state do. He advises seeking shelter inside somewhere.

“I don’t recommend going out and about at those times,” Samac said. “That is when you are probably going to get caught. Get inside the closest structure you can find. These things usually blow over in a half hour unless there is a big front of storms coming in.”

Inside, look for a place that has a lot of structure to it like center hallways, bathrooms, basements or storm cellars. Basements or storm cellars are probably the safest because the top of the building could be blown off, but the basement left intact.

Some local residents have speculated that Eureka Springs is less vulnerable to tornado damage because of its hilly terrain surrounded by mountains. Turns out there is some research to support that hypothesis.

  1. Panneer Selvam, Ph.D, P.E., a civil engineering professor at the University of Arkansas in Fayetteville who has studied tornadoes since 1982, said he watched the storm front come in from Oklahoma on April 30.

“That was a very bad day,” Selvam said. “I was watching the whole thing how the storm was moving. Fayetteville, like Eureka Springs, is surrounded by hills. Usually when storms come to our area, they get defused by the mountains. Basically, my research of the Mayflower and Joplin tornadoes has shown that there is less damage in hilly places. In flat areas, the damages are much higher.”

Selvam said his studies have also found that tornadoes tend to take the path of least resistance path when crossing hills and cause more damage on the uphill side. If the hills are close together, the tornado may skip the valley between the hills.

While Eureka didn’t experience a tornado on April 30, the county has had quite a few disaster declarations in the past year or so. There was a tornado that did major damage in Wolf Ridge and another that took down a large number of trees and caused some building damage in the Hogscald area.

And with storms, there are often torrential downpours. Samac said there was quite a bit of water damage this past weekend from all the rain.

“There is a bridge on CR 705 that is washed out right now,” Samac said. “My driveway is even washed out.”

Some parts of the region have seen record rainfall this year. The National Oceanic and Atmospheric Administration (NOAA) said this past winter was the wettest on record for the contiguous U.S.

“Rainfall records for the month of February were observed in Knoxville, Tennessee (13.08 inches), Nashville (13.47 inches), Bristol, Tennessee (10.47 inches), Tupelo, Mississippi (15.61 inches), Muscle Shoals, Alabama (14.13 inches), and Huntsville, Alabama (13.63 inches), with widespread flooding occurring along rivers and tributaries as well as mudslides impacting travel for many,” NOAA said.

Due to what has been described as “relentless rainfalls,” parts of the Mississippi River have been in flood stage more than 30 days, and flooding is expected to continue through June. The Mississippi River also crested in some areas at higher levels than ever recorded.

NOAA indicated rainfall in Northwest Arkansas this past winter was much above average.

After the storm April 30, one local resident who has lived here for 50 years said he couldn’t remember seeing so many tornadoes form almost at once. Climate change experts have predicted more severe weather events due to climate change caused by the release of greenhouse gases.

“The science is nascent, but early results suggest that tornadoes and severe convective storms that produce tornadoes will become more frequent, but also more variable,” Walker Ashley, an atmospheric scientist at Northern Illinois University who specializes in risk and vulnerability to extreme weather events, said in an article published in Scientific American.

“Recent climate research has revealed an intensification in the year-to-year variability and clustering of tornado counts, as well as the potential for increasingly frequent and more variable environments supportive of severe convective storms and their hazards due to anthropogenic climate change,” Ashley and Stephen Strader of Villanova University wrote in a 2016 article for the Bulletin of the American Meteorological Society.