What would Chicago’s weather be without the Rocky Mountains?
In the absence of the Rocky Mountains, familiar hallmarks of Chicago’s climate would be gone. “Panhandle hook” storms and “clippers” that sweep into the Midwest from their birthplaces in the lee of the Rockies would not occur. The abrupt day-to-day temperature changes that frequent the city and the huge ranges of temperature between summer’s heat and winter’s chill would be reduced. The existence of these weather events is testament to the Rockies’ weather-producing capabilities. Parallel to North America’s west coast and perpendicular to the prevailing westerlies, the Rockies inhibit the eastward movement of mild Pacific air and encourage the latitudinal motion of arctic and Gulf air masses.