On May 23, 2011 a strong supercell thunderstorm moved across northern Kiowa County producing large, damaging hail. A hail research team (HailSTONE) recovered a large hailstone 2 miles north of Gotebo, OK that measured 6 inches in diameter.
The hailstone was so large that it significantly caved in the roof of the vehicle that captured it. Investigation and coordination between the National Weather Service in Norman, OK and the Oklahoma Climatolgical Survey (OCS) determined that this is the new record holder for largest hailstone in Oklahoma.
Read more about the storm here.