On Friday, December 3, 1999, during the late evening hours severe thunderstorms formed over northeast Oklahoma and moved into southwest Missouri. A weak boundary was present near the Joplin area. Shortly before 9:30 PM CST, a radar-indicated tornado warning was issued for Newton and Jasper counties. Although no touchdown occurred, a wall cloud was reported northeast of Neosho. As the storm approached western Lawrence County, an additional tornado warning was issued around 10:00 PM CST. In the county, golf ball-sized hail was reported in the community of Miller. Later that evening in the Seneca area, spotters and local law enforcement reported nickel-sized hail covering the ground, accumulating up to three inches deep. Again that evening, another tornado warning was issued for Greene and Polk counties after spotters reported a wall cloud and later a funnel near the community of Everton. Although no touchdown occurred, large hail was reported in Walnut Grove. Despite the weak frontal boundary, severe thunderstorms formed along it and moved into a cooler air mass. While large hail was the primary threat with most storms, a few storms became right-movers, which contributed to tornado development. By the time the event concluded between 9:00 PM and 1:00 AM, a total of 16 severe thunderstorm warnings and 3 tornado warnings had been issued by the National Weather Service in Springfield, Missouri.
Source: NWS Springfield, MO