US fatalities in tornadoes top 90 as scientists clarify their formation

NEW YORK (Xinhua) -- US state of Kentucky is awaiting President Joe Biden who is scheduled to survey tornado damage, meet with victims and deliver remarks there on Wednesday, manifesting that the federal government has attached much attention to the disaster that has claimed at least 90 lives across six states in the central parts of the country.

A town water tower is seen destroyed in the aftermath of a tornado in Mayfield, Kentucky, US.

The president’s trip will include a stop in Fort Campbell for a storm briefing, and stops in Mayfield and Dawson Springs to survey storm damage. Compared with Arkansas, Illinois, Missouri, Mississippi and Tennessee, Kentucky was the hardest hit with more than 80 deaths aged from 2 months to 98 years, and over 100 unaccounted for.
Meanwhile, in Edwardsville, Illinois, the Occupational Safety and Health Administration is investigating the deadly collapse at an Amazon warehouse, which was caused by a tornado on Friday that devastated the area and killed six Amazon workers. Most workers who died there were not sheltering in the “designated location,” the company said.
More alarmingly, CBS reported on Tuesday that the cluster of deadly storms occurring on Dec. 10 to 11 is the latest sign that “tornado activity has waned in the Great Plains - historically known as ‘Tornado Alley’ - while picking up in the southeastern US, a manufacturing-rich region increasingly critical to the nation’s supply chain.”
Tornado Formation
Amid the catastrophe, the early signaling systems placed throughout the middle of the country mostly worked as promised, reported The Wall Street Journal on Tuesday. People received text alerts and radio alerts from local officials and forecasters, which would have given them enough time to shelter in place, as they have done for years during tornadoes.
However, the power, speed and duration of the tornado caught residents, businesses and cities by surprise and overwhelmed many of their safety procedures. The tornado’s estimated wind speeds of over 200 miles an hour would make it an EF5, the highest level on the Enhanced Fujita scale rating system, according to the report.
While meteorologists continued to analyse data on the tornado, its length was likely record-setting. “It sent debris 30,000 feet into the air, the cruising altitude of many passenger jets, and scattered prom photos, handmade quilts and wrapped Christmas gifts scores of miles away from the tornado’s path,” said the report.
The twister rivaled the 1925 Tri-State tornado that killed 695 people as it traveled 219 miles across Missouri, Illinois and Indiana. Bill Bunting, chief of forecast operations at the National Weather Service’s (NWS) Storm Prediction Center, was quoted as saying that a rare confluence of weather conditions created the tornado.
First was the development of a supercell, an enormous weather system generating severe thunderstorms and rotating upward currents of wind. That combined with an unusually steady muggy environment, with temperatures hovering in the low 70s over the course of several hours. Moreover, no other major storms formed to disrupt the tornado’s formation or block its path, according to Bunting.

(Latest Update December 17, 2021)