How long have Chicago’s temperature and precipitation records been kept?
Chicago’s official weather records began on Nov. 1, 1870, under the jurisdiction of the United States Army Signal Service within the Department of War.
The “Division of Telegrams and Reports for the Benefit of Commerce,” as the National Weather Service was first called, was established by a joint resolution of Congress and signed into existence by President Ulysses S. Grant on Feb. 9, 1870.
At the time, the Chicago office was one of twenty offices that began operation in the United States. The agency was renamed the Weather Bureau in 1890 and transferred to the Department of Agriculture, then to the Commerce Department in 1940.
Its name was changed to the National Weather Service in 1970.