NU Online News Service, Feb. 21, 2:58 p.m. EST
After a near-record number of tornadoes in 2011, this year is gearing up to be another active season, according to AccuWeather.com.
The weather service says that climatic activity last year produced a near record year for tornadoes with a total of 1,709, making it the fourth most deadly tornado year in the United States. The record was set in 2004 with 1,817 tornadoes. The average is 1,300.
A strong La Niña phenomenon last year, with sea surface temperatures in the central and eastern Pacific around the equator below normal, produced a very strong jet stream. This is a key ingredient for severe weather.
In the La Niña year, the normal tornado pattern shifts east, causing many twisters to hit from Texas to Kansas, say the forecasters. The phenomenon causes warmer-than-normal Gulf of Mexico waters, like last year, and is expected to be a key component to another active tornado season this year.
This year, the La Niña appears to be weaker which may mean near normal temperatures in the central and eastern equatorial Pacific by spring.
“Areas that seemed to miss out on frequent severe weather last year may see an uptick this year,” says Dan Kottlowski, AccuWeather.com expert senior meteorologist.
The Deep South should not experience the severe outbreak of tornadoes as last year, but that does not mean the Gulf States will avoid damaging thunderstorm and tornado activity.
Severe weather could affect the region through March, but the severe weather threat should move north into Ohio and the mid-Mississippi valley in early April.
“If I were in the South or OhioValley, I’d be extra prepared this year,” Mike Smith, senior vice president of AccuWeather Enterprise Solutions cautioned.
Whether tornadoes hit highly populated areas like they did last year is harder to pinpoint, AccuWeather says.
According to the National Oceanic and Atmospheric Administration’s NationalClimateDataCenter, in January of this year there were 95 tornadoes, well above the 1991-2010 average of 35. It will likely be the second busiest January on record, NOAA says.