US reacts to spate of tornadoes as weather expert explains their formation

New York, Dec 14 (SocialNews.XYZ) The tornadoes that ripped through six US states, namely Arkansas, Illinois, Kentucky, Mississippi, Missouri and Tennessee, over the weekend have killed scores of people, leveled entire towns and left recovery teams facing weeks of clearing rubble, while scientists are assessing the once-in-a-century levels of destruction on a swath extending 250 miles, according to US media.

"The storm may also end up as one of the deadliest in US history," The Wall Street Journal reported on Monday. In one town of 2,700 people, Kentucky Governor Andy Beshear told NBC's "Meet the Press" on Sunday, the list of residents who were unaccounted for was eight pages long. At least 56,000 people in Kentucky were without power, and houses in many places were missing roofs, doors and windows, according to the Governor.

In all, the National Weather Service received reports of 37 tornadoes across these six states. Though it may take several more days before scientists can officially assign severity rankings to the tornadoes, they said debris might have been hurled as high as 30,000 feet into the air, the cruising altitude of many passenger jets. Meanwhile, the total fatality is yet to top 100 and may end up less than initially feared, Xinhua news agency reported.

US President Joe Biden approved federal funding over the weekend to help parts of Kentucky hammered by the deadly tornadoes, with a disaster declaration for the state following a request from its Governor. The spate of tornadoes that struck six states included one that hit Kentucky the hardest. Beshear said "the storm event was the longest tornado track on record and the largest in Kentucky history."

The declaration makes federal funding available for storm victims in the western Kentucky counties of Caldwell, Fulton, Graves, Hopkins, Marshall, Muhlenberg, Taylor and Warren, as well as for state and "eligible local governments and certain private non-profit organisations on a cost-sharing basis for emergency work" there, a White House news release said on Sunday.

The assistance available to residents affected by the storm includes "grants for temporary housing and home repairs" and "low-cost loans to cover uninsured property losses." Biden also ordered federal aid to supplement recovery efforts. He said on Saturday that his administration is "ready to do the same for the Governors of the other states" affected by the storm if they request an emergency declaration.

A combination of the main tornado's enormous path as it tore from Arkansas to Kentucky, its sheer power and the high number of smaller whirlwinds that accompanied it made for an overwhelming force that left devastated communities in its wake. December tornadoes are uncommon but not unheard of, but the explosion of twisters across the states over the weekend might be unprecedented, reported USA Today on Monday.

"Tornadoes do happen at this time of year, but the number in which they happened and the intensity in which they happened Friday night is what is rare," Dan DePodwin, Director of forecast operations for weather forecasting services provider AccuWeather, was quoted as saying. "On average, in December, there are roughly two dozen tornadoes (nationwide). We're going to surpass that just on the one night Friday."

A three-year average of 47 tornadoes has been reported in the US during December, according to the Storm Prediction Center. The multi-state outbreak is shaping up to be unusual, especially in how much farther north than usual it occurred. In addition, the number of fatalities that the outbreak may have caused is exceptionally rare, as the month of December rarely sees tornado fatalities at all.

"The unusual warmth in the north that preceded the outbreak was one of the main ingredients that drove it to occur. It's typically not so warm this time of year for that region, so outbreaks are usually unable to form," reported AccuWeather on Sunday, while quoting DePodwin as saying that "I think the warm December certainly played a role. We haven't had a lot of cold fronts make their way all the way down into the Gulf of Mexico yet."

The Gulf of Mexico being at or above normal this time of year can further aid in the transport of warmer air northward, which is what helped fuel the multi-state outbreak. As the warmer air from the Gulf moved north, a very strong low pressure area was moving out of the Rockies and into the Great Lakes region. This pulled the warm and moist air even farther northward, said AccuWeather.

Four main ingredients needed for severe weather were prevalent to ignite the outbreak, DePodwin said, adding that "you need moisture, which we had from the Gulf of Mexico. You need instability, rising air. You need colder air aloft, we had that. You need some type of lifting mechanism, a cold front in this case. And then you need some type of turning in the atmosphere or wind shear, as we call it."

Source: IANS