Climate of Chicago
Official locations
Table:
Dates
Location

Remarks

October 15, 1870 – October 8, 1871
181 W. Washington St.
All records lost due to Great Chicago Fire

October 15, 1871 – June 11, 1872
427 W. Randolph St.

June 11, 1872 – June 8, 1873
20 N. Wacker Dr.

June 8, 1873 – January 1, 1887
Roanoke Building

January 1, 1887 – February 1, 1890
Chicago Opera House

February 1, 1890 – July 1, 1905
Auditorium Tower

Automatic rain gauge installed in 1897

July 1, 1905 – December 31, 1925
U.S. Court House

Supplemental observations through 1970

January 1, 1926 – June 30, 1942
University of Chicago

Supplemental observations through 1962

July 1, 1942 – January 16, 1980
Midway Airport

Continues to provide observations

January 17, 1980 – present
O'Hare Airport

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