FAYETTEVILLE, Ark.–Mississippi has more than its share of deadly tornadoes and though 2013 has been a relatively quiet year, an intense tornado has the potential to form if the conditions are right. New research coming from the University of Arkansas suggests that tornadoes may actually be more dangerous in some situations and less dangerous in others.
For instance, the new report says twisters do more damage when traveling uphill. And more tornadoes climb hills than go down them.
The same research concludes that when tornadoes are in an area surrounded by hills, they tend to skip over the valleys and damage is noticed on the hilltops rather than down below.
The research was done by civil engineering professor Panneer Selvam and civil engineering graduate student Nawfal Ahmed and considered only the 2011 EF4 Tuscaloosa and the EF5 Joplin tornadoes. The professors concluded that most tornadoes would follow the patterns.
Not so, says Weather Channel expert Dr. Greg Forbes, who was on the team that developed the Fulita scale (F1, F2 and so on). On the Weather Channel website he said his research says something else.
“The results of this study do not seem to be ‘universal’ in that they disagree with most previous studies, including some of those by Fujita and some of my own,” said Dr. Greg Forbes. “Of course, every tornado can have its own behavior.”
Dr. Forbes also points out that tornadoes are not nearly as common in mountainous areas as they are in the Plains.
“Most studies have shown that tornadoes get somewhat more diffuse, but sometimes wider, as they climb mountain slopes. Sometimes multiple inflow swaths of damage emerge in the process,” said Dr. Forbes. “The tornado sometimes then re-intensifies if it reaches an elongated plateau at higher elevations. It has more commonly been observed that tornadoes intensify and get more narrow (i.e., become more concentrated) as they descend mountain slopes – somewhat in the same sense as a bathtub vortex intensifies as water is pulled down the drain.”