Forecasters gave an official rating of EF4 to Sunday’s tornado that demolished homes and businesses Sunday, killing 11 people in Mayflower and Vilonia.
The storm was rates as a "high-end" EF4 on the scale of tornado strength with winds between 166 and 200 mph.
Fifteen people in Arkansas were killed.
Arkansas hasn’t had a top-of-the-scale storm since April 10, 1929, when a twister formed south of Batesville in Independence County and struck Sneed in northern Jackson County. That storm was rated F5 on a previous scale and killed 23.
Sunday’s death toll of 15 was the state’s highest since 1997, when 25 people were killed in storms that tracked from Arkadelphia to the Missouri Bootheel.