A seemingly relentless series of severe storms, likely accompanied by deadly tornadoes, are expected to sweep through parts of the Midwest and South America over the next two weeks, particularly Friday, meteorologists said.
An unusual weather pattern set in, triggering last week the devastating tornado that struck Rolling Fork, Mississippi, and meteorologists fear this Friday could be one of the worst days, with much more to come. The National Weather Service said 16.8 million people live in the high-risk zone, and more than 66 million people in total are expected to be on alert Friday.
“It’s very clear that someone is going to take it on the nose on Friday,” said Victor Gensini, a northern Illinois meteorology professor and expert and tornado hunter. “It’s just a matter of where and when exactly.”
The weather service warns much of the country – including parts of Iowa, Missouri, Arkansas, Illinois, Indiana, Kentucky, Tennessee, Mississippi, Alabama, Louisiana, Alabama , Texas, Oklahoma, Ohio, Wisconsin, Minnesota, Michigan, West Virginia, Georgia and Kansas thunderstorms, tornadoes and other damaging winds. The major cities in the most dangerous area are Memphis, St. Louis, Des Moines and Little Rock.
Gensini fears Friday’s attack could be deadly.
The storms are expected to start Friday afternoon and last overnight, which is especially dangerous because people can’t see them coming and often don’t seek shelter, the weather forecasting center’s warning coordination meteorologist said on Wednesday. Matt Elliott storms.
“Storms will move very quickly,” Elliott said. “So you won’t have much time to react to warnings either. Now is the time to start preparing.
While all the ingredients are there for dangerous storms, they may not combine precisely enough to pose the threat meteorologists warn of, Elliott and others said.
Another round of severe storms, fueled by a ‘fire hose’ of unstable waves in the atmosphere that continue to flow from the cold west and combine with moist air from the east, could hit next Tuesday. and the following days, said Walker Ashley, another northern Illinois meteorology professor and Gensini’s storm chasing partner.
“You could see these things coming days in advance,” Ashley said. It will be “continuous punches, one, two, three, four”.
The weather service is already predicting another batch of intense storms next Tuesday in the same general area as Friday with fairly high confidence, Elliott said.
At least the first 10 days of April will be difficult, said Accuweather meteorologist Brandon Buckingham.
The current lingering pattern of storm ingredients reminds Gensini of the April 2011 tornado attack which killed 363 people in six states, hitting Alabama the hardest. It was one of largest, deadliest and most destructive tornado outbreaks in American history, the weather service said.
Even before Friday, “it was the most active we’ve seen in several years” from around last november, with a large number of winter storms this year, Elliott said. The killer storms that hit Rolling Fork were part of this pattern.
Buckingham and the other meteorologists said the current conditions only come around once every few years to create the potential for a train of supercells, which spawn the worst tornadoes and devastating hail.
At the center of this is a fast, roller coaster-like jet stream, the moving river of air that moves weather systems, such as storms, from west to east. On the west side of the jet stream is extremely cold air and to the east, off Florida and the Caribbean, is a very hot and dry high pressure system.
“When you combine the two, it causes those hairs on the back of your neck to stand on end,” Buckingham said. “The ingredients are there. They are primed towards the extreme end of things.
Add to that the Gulf of Mexico, which provides moisture, heat and energy for storms, about 2 to 5 degrees (1 to 1.5 degrees Celsius) warmer than average or hotter, meteorologists said — “on fire,” as Ashley put it.
“The extra heat and humidity really triggers these thunderstorms,” Buckingham said.
The worst weather will be “shocked” by hot and cold air, a battlefield of sorts, Gensini said. Friday’s forecast for lunch in Storm Lake, Iowa, is around 67 degrees (19 degrees Celsius), but just 140 miles (225 kilometers) northwest, Brookings, South Dakota, should be just above freezing point.
“The higher the temperature gradient, the stronger the storm systems,” Gensini said.
Winds swirling in opposite directions to the west and east of the jet stream’s battlefield add to the problem, meteorologists said.
Ashley said the current conditions are mostly random weather variability, although he said the warmer Gulf of Mexico and human-caused climate change may have made a small contribution.
“Those events have always happened,” Ashley said. “The question is, are we turning the knob a bit by bringing in more humidity, more heat, more instability?”
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