Oklahoma’s extremely cold winter last year and earlier this year likely kept the number of tornadoes this past spring at the state’s lowest levels since 1988, weather experts say.
Only 13 tornadoes hit the state through June, which is the latest available data. And only one — an April tornado in Quapaw that killed one person — had any significance, Greg Carbin, warning coordination meteorologist with the Storm Prediction Center told the Tulsa Word.
Carbin said researchers have found a correlation between especially cold winters or hot summers and low tornado counts.
“One factor that played into lower tornado totals were the cooler temperatures during winter and in late winter,” Carbin said. “But that flips around in the summer, higher temperatures usually correlate with less tornadoes.”
The 13 tornadoes on record through the first six months of 2014 is the lowest total in Oklahoma since 1988, when just 10 were documented during the same time frame, according to meteorologist Doug Speheger.
“I believe that those are the only years on record since the modern era of tornado documentation in 1950 that Oklahoma has had that few tornadoes in that time period,” Speheger said.
Oklahoma is not alone in the low number of tornadoes this year. It was mirrored across the country. There were only 152 EF1 or stronger tornadoes recorded in the U.S. through May, according to National Weather Service data. That’s the lowest number since 2005, when 105 tornadoes of the same strength were recorded.
For comparison, 741 EF1 or stronger tornadoes were recorded in 2011, a particularly active year. Carbin said active years nationally usually require a confluence of events that is often rare.
“It’s going to take a number of things,” he said. “It’s not just an active spring (that raises the totals). You have to have an active early spring and an active fall. If you’re going to have high numbers, it has to be all year. If you suppress it for one season, you can suppress the entire year’s total.”