Tornadoes put 5 million people in the US at risk 0:49
(CNN) -
There is an alert for night tornadoes in the United States and the threat level of severe storms has increased to a level 4 of 5 for more than 2 million people, according to an update from the Storm Prediction Center (SPC). for its acronym in English).
The area is centered on the confluence of the Ohio and Mississippi rivers and includes Memphis.
The Tier 3 of 5 risk was also expanded and now covers more than 15 million people, including Nashville, St Louis, Louisville, and Indianapolis.
More than 5 million people in the United States should prepare for possible nighttime tornadoes
According to the SPC, "the overwhelming majority of strong-severe convection should occur after dark," making this situation especially dangerous.
Nighttime tornadoes are 2.5 times more deadly than daytime tornadoes, according to a study.
"The main concerns will be occasional tornadoes capable of causing EF2 + damage and scattered and damaging storm bursts," according to SPC.
Beyond the level 3 risk area, a much higher level 1 and 2 risk out of 5 extends from the Great Lakes to the Gulf Coast.
This includes Chicago, Houston, Indianapolis, Shreveport, and Cincinnati, where severe weather is not expected to be as widespread, but is still possible.