In an area that covers St. Louis, Chicago, Detroit, Cincinnati, Pittsburgh, Roanoke and Washington DC, a dangerous severe weather outbreak is poised to strike. People living in portions of the Midwest and Ohio Valley and eastward are being warned by meteorologists that they are at a very high risk for some troubling weather. In addition to severe thunderstorms which are poised to sweep across that part of the country, there is a very real threat of a derecho developing.
A derecho is a weather event that only happens a couple times a year. A derecho is a wind storm that has wind speeds of at least 75 miles per hour and which can be as stronger than 100 miles per hour. The conditions are just right in the Midwest for a derecho to occur. This type of rare weather system forms quickly, much like a tornado does, making it hard to predict. These types of storms can maintain their intensity for several hours as they roll across vast distances. They also can spawn tornadoes and large, damaging hail.
Meteorologists are warning people living in an area that spans form South Dakota to Pennsylvania that they’re at a high risk for very severe weather. The National Weather Service said early Wednesday that the gigantic line of very powerful storms that are bearing down on the Midwest and areas further south and east could affect one-fifth of all Americans. The average tornado at the low end of the rating system can pack winds between 85 and 100 miles per hour as it moves across a relatively small area. A derecho however tends to deliver the vast majority of extreme wind over much of the region in which it occurs to put millions and millions of people at risk.
Meteorologists are warning that Wednesday could be the worst severe weather outbreak for the Midwest all year. It was about one year ago when a derecho hit the country that covered a wide area stretching from Chicago to Washington. That weather event killed more than a dozen people who were hit by downed trees. More than thirty more were killed in the heat wave that followed in those areas which lost power.