How The Great Lakes Form Chicago Weather

Chicago wouldn't be Chicago without the Lake Michigan climate. Chicago's position on the lake's southwest shore allowed the city to develop quickly after its incorporation in the 1830s into a center of production, shipping and railroading.

Lake Michigan in addition has helped Chicago weather to be identified all over the world as blustery, freezing and home to some magnificent winter storms, with the latest blizzard in February making the record books as the third-largest in the Windy City's history.

The following is a brief briefing on how and why Lake Michigan and the other Great Lakes have such a significant impact on Chicago weather.

The five Great Lakes (Michigan, Huron, Superior, Erie, and Ontario) generally act as a large heat sink, moderating the temperatures of their shores. The lakes also are giant humidifiers, raising the amount of moisture that floats in the air all year round.

Which means that in the winter, this significant moisture condenses and will become snow when it hits shore, making what are known as "snow belts" on the downwind lake shores.

Cities on the downwind sides of the lakes such as Cleveland, Ohio; Erie, Pennsylvania; and Buffalo, New York (Lake Erie); Syracuse, New York (Lake Ontario); etc. generally get what is known as "lake effect" snow, receiving way more snow than other locations on the same latitude. For example, some areas along the shore of Lake Superior have recorded snowfall of up to 350 inches in just one year!

Yet Chicago weather isn't really impacted by lake effect snow resulting from the fact that the existing westerly winds that cross the region take on moisture from Lake Michigan after moving through (some would say through) Chicago.

That's not to say that the Lake Michigan climate doesn't sometimes drop a significant level of snow on Chicago. The uncommon northeasterly winds occasionally do bring on the kind of blizzards that are so popular in snow belt towns.

Sheila Dodd is the Marketing Executive for Chicago based motor coach company Executive Coach. Along with city and Midway Airport transportation, Executive Coach also offers services for group sightseeing in Chicago and day trips from Chicago. For more information on charter bus or shuttle rental, please visit www.ExecutiveCoachofChicago.com or call (708) 352-9780 to speak with a representative.