Morris, IL Climate

Climate Insight: Morris, IL

An annual average temperature of 51°F, ranging from a mean daily high of 60°F to a mean daily low of 41°F is what the NOAA 1991–2020 climate normals report for Morris, Illinois. July is typically the warmest month of the year, while January is the coldest. That baseline comes from station USC00115825 and thirty years of averaging, so it reflects a typical month rather than any one year's swings.

Anyone planning to live, garden, or travel in Morris should weigh precipitation alongside temperature: the annual average runs 38.8 inches, with 24.7 inches typically falling as snow. The frost-free season averages 186 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 20 and the first fall freeze near October 23. And on the energy front, 6,141 heating degree days and 995 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Morris scores 63/100 (Good), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. The monthly tables above turn that into a planning tool: expect the mildest highs and lows in the shoulder seasons, July-driven heat at the peak of summer, and January-driven cold at the depth of winter. Every number here is a thirty-year average, not a forecast, so any given year can and does run warmer, cooler, wetter, or drier than the normal.