sentence: The Great Lakes have a humid continental climate , Köppen climate classification Dfa -LRB- in southern areas -RRB- and Dfb -LRB- in northern parts -RRB- with varying influences from air masses from other regions including dry , cold Arctic systems , mild Pacific air masses from the West , and warm , wet tropical systems from the south and the Gulf of Mexico .
question: where is something influencing something _ _ ?
answers: The Great Lakes