Nine tornadoes are found in the SPC Database for July 21, 1983. The strongest was rated F3 in Ocean County, NJ. The deadliest though was an F2 that briefly hit the northern parts of Hartly in Kent County, DE.
Per the Storm Data Publication, this was the first tornado to hit in Delaware during the winter months (December through February). The twister moved to the northeast for only 1/2 mile. Four houses were destroyed.