The Jets won the 68-69 Superbowl, so I say it is 3 champs in two years.
Azraek, “Any other cities won 2 or more championships in the same year?”
1987-88 LA Lakers, 88 Dodgers
1984-85 LA Lakers, 84-85 LA Raiders (The Reagan years were good for LA).
1979 Pirates, 1979-80 Steelers, (Steelers won in 1980-81, also).
1968-69 Jets, 1969 Mets, 1969-70 NY Nicks
However, LA and NY usually have two teams in each of the sports (Dodgers and Angels, Raiders and Rams, Mets and Yankees, Islanders and Rangers,…), while the other cities usually only have one team per sport, like Pittsburgh does. So, the Pittsburgh double championship is the most impressive.