Tornados a source of concern for Southern states, say weather experts

astice@islandpacket.comMarch 5, 2012 

Strong winds continued Monday in the Lowcountry following a weekend of heavy rains, the aftermath of a weather system that caused deadly tornadoes from Indiana to Alabama and signaled the start of the South's 2012 tornado season.

Twisters killed 39 people across five states Friday, with one storm-related death reported in Georgia, according to The Associated Press.

Most of the death and destruction occurred in the Midwest -- communities in Indiana the hardest hit -- where it is uncommon for tornadoes to touch down this time of year, according to Michael Emlaw, head meteorologist with the National Weather Service in Charleston.

"What was unusual, besides the magnitude and severity, was the fact that it was so far north," Emlaw said. "This time of year, it's very common to have tornadoes in the South."

Tornado season in Southern states typically begins in February and peaks in April. That's because twisters and other kinds of severe weather surge from the clash of warm, humid air -- common in the South in early spring -- and the cooler temperatures that remain in the North, Emlaw said. Strong winds are another key ingredient.

By contrast, April through June is tornado season for the rest of the United States.

It's difficult to predict the number of storms or tornadoes a season will produce.

Accuweather meteorologist Frank Strait said his company's long-term forecasting team predicts more storms than average this season, but fewer than in 2011.

There were nearly 1,700 tornadoes in 2011, which also was one of the deadliest years on record, with 550 deaths, according to the National Weather Service. The average over the past decade is around 1,300 tornadoes a year.

"We're only forecasting general trends, because we can't really come up with specifics more than several days away, but we're thinking this will be another busier-than-normal season," Strait said.

Strait said conditions this year should be similar to 2011, including an ongoing La Nina, which causes lower-than-normal temperatures along the equatorial sea surface. La Nina also creates a strong jet stream, which can pull moisture up from the tropics and is "conducive to tornadoes forming," Strait said.

Emlaw with the National Weather Service in Charleston said it's difficult to tell what the rest of the season will bring.

Friday's tornado devastation, however, is a "bad start to the year," he said.

Follow reporter Allison Stice at twitter.com/LCBlotter.

Related content

The Island Packet is pleased to provide this opportunity to share information, experiences and observations about what's in the news. Some of the comments may be reprinted elsewhere in the site or in the newspaper. We encourage lively, open debate on the issues of the day, and ask that you refrain from profanity, hate speech, personal comments and remarks that are off point. Thank you for taking the time to offer your thoughts.

Commenting FAQs | Terms of Service