Which county in Florida is the third-most populous and is north of Deerfield Beach?
Deerfield Beach, Florida:  It is located just south of the Palm Beach County line. Palm Beach County, Florida: Palm Beach County is a county located in the state of Florida, directly north of Broward County. Palm Beach County, Florida:  As of the 2010 census, the population was 1,320,134, making it the third-most populous county in Florida.
Palm Beach County