The largest band of severe weather stretches from Texas through Oklahoma, Arkansas, Missouri, Tennessee, Kentucky, southern Illinois, Indiana and West Virginia, where more than 15 million people will be affected, according to the forecast.
According to the weather agency, the main threat is freezing rain, which can create major hazards by covering roads, power lines and tree branches.
Parts of central Texas near Austin could see more than a half-inch of ice buildup, prompting local authorities to close some schools in those areas.
In the southwestern states, extreme weather advisories were also issued and in Denver, Colorado, a record of 38 years was reached with a minimum of minus 10 degrees, warned The Hill.
Meanwhile, in other parts of the country, like North Dakota, records point to temperatures below freezing, with severe cold and low wind chill.