section_path: Climate
section_name: Climate
paragraph_text: Climate
  
  The Great Lakes have a humid continental climate, Köppen climate classification Dfa (in southern areas) and Dfb (in northern parts) 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. The lakes have a moderating effect on the climate; they can also increase precipitation totals and produce lake effect snowfall.