Subtropical areas have hot, humid summers and mild winters, but less extreme than the tropics. Miami experiences subtropical weather, with long summers and short winters.
Pro Tip 2/3
Not Equatorial
Remember, subtropical isn't the same as tropical; it's less hot and less consistent rainfall. The Azores islands have a subtropical climate, not a tropical one.
Pro Tip 3/3
Geographic Use
Use 'subtropical' to describe geographical areas just north or south of the Tropic of Cancer or Capricorn. Parts of Australia are subtropical, situated just below the Tropic of Capricorn.