Illinois State Water Survey - University of Illinois at Urbana-Champaign

State Climatologist Office for Illinois

Climate Change Maps for the United States

While not a widely discussed topic in climate change, the U.S. exhibits regional differences in historical temperature trends. In general, the western half of U.S. has experienced strong warming while the southeastern U.S. experienced some degree of cooling. Illinois lies between these contrasting regions. As a result, while Illinois has experienced some warming it has been milder than many western states.

These figures are the linear temperature trends for the U.S. in degrees Fahrenheit, expressed as the change over the period 1895-2006, as derived from climate division data. The first figure is the annual temperature followed by the four traditional seasons of winter (December-February), spring (March-May), summer (June-August), and fall (September-November).

Annual temperature trends for the US


 

Winter temperature trends for the US


Spring temperature trends for the US

 


Summer temperature trends for the US

 


Fall temperature trends for the US