St Jacob is located in Illinois. St Jacob, Illinois has a population of 1,290. St Jacob is more family-centric than the surrounding county with 49.87% of the households containing married families with children. The county average for households married with children is 29.92%.
The median household income in St Jacob, Illinois is $70,833. The median household income for the surrounding county is $56,536 compared to the national median of $57,652. The median age of people living in St Jacob is 33.5 years.
The average high temperature in July is 88.8 degrees, with an average low temperature in January of 22.3 degrees. The average rainfall is approximately 41.9 inches per year, with 12.1 inches of snow per year.