In recent years, average temperatures in the county seat of Quincy have ranged from a low of in January to a high of in July, although a record low of was recorded in January 1979 and a record high of was recorded in July 2005. Average monthly precipitation ranged from in January to in May.
Demographics
As of the 2010 United States Census, there were 67,103 people, 27,375 households, and 17,677 families residing in the county. The population density was. There were 29,842 housing units at an average density of. The racial makeup of the county was 93.7% white, 3.5% black or African American, 0.7% Asian, 0.2% American Indian, 0.4% from other races, and 1.6% from two or more races. Those of Hispanic or Latino origin made up 1.2% of the population. In terms of ancestry, 43.5% were German, 13.1% were Irish, 10.7% were American, and 8.7% were English. Of the 27,375 households, 29.9% had children under the age of 18 living with them, 50.0% were married couples living together, 10.7% had a female householder with no husband present, 35.4% were non-families, and 30.1% of all households were made up of individuals. The average household size was 2.37 and the average family size was 2.94. The median age was 40.7 years. The median income for a household in the county was $43,824 and the median income for a family was $55,791. Males had a median income of $38,830 versus $29,371 for females. The per capita income for the county was $24,308. About 8.3% of families and 12.3% of the population were below the poverty line, including 17.5% of those under age 18 and 8.1% of those age 65 or over.
Adams County, positioned in a primarily rural section of Illinois is culturally isolated from Chicago, and therefore more conservative than the state's northeastern corner. Quincy, the county seat, holds a high number of socially conservativeCatholics and likewise is the home to the campus of Quincy University, a private Catholic liberal arts college, and the Western Catholic Union. The county is part of the historic belt of German settlement extending into the Missouri Rhineland. Since it was antagonistic to the Yankee northeast of Illinois, it voted solidly Democratic until 1892. After being a swing county in the first half of the twentieth century, Adams County has been a Republican stronghold. It has gone Republican in all but five presidential elections since 1920. The county last supported a Democxrat in 1964, when it voted for Lyndon Johnson. The county regularly rejects Democrats at the state level as well; it has not supported a Democrat for Governor of Illinois since Adlai Stevenson II in 1948, and there are no elected Democrats above the county level. Notably, while it voted for Barack Obama in his 2004 Senate campaign, he lost it by wide margins in both of his presidential bids. The county is part of Illinois' 15th congressional district, currently represented by Republican Darin LaHood. For the Illinois House of Representatives, the county is located in the 94th district, represented by Republican Randy Frese. The county is located in the 47th district of the Illinois Senate, represented by Republican Jil Tracy.
