Seasonal Trends in Illinois Temperature and Precipitation

These figures reveal that climate change can differ by season in Illinois. In general, the largest changes have occurred in winter temperatures. As is typical of a mid-continental climate, all four seasons of both temperature and precipitation experience a large degree of variability from year to year and decade to decade. This makes the detection of long term climate trends even more difficult.

Precipitation

Note: the red line in these figures is a 5-year moving average to filter out some of the year-to-year variability.