The 5 Coldest Places in Illinois Will Chill You to Your Core

While Illinois may not be one of the top 10 coldest states in the country, its record coldest temperature of -38 degrees Fahrenheit means winter in the Prairie State is no joke. Illinois is mostly flat, open prairie land, making it susceptible to incursions of bitterly cold air masses from the Arctic in winter. With no mountains to the north and south of the state, its location in the interior of North America also exposes Illinois to humid air masses from the Gulf of Mexico in the summer. These weather patterns mean summer and winter temperatures vary widely. Average winter highs are in the 30-degree Fahrenheit range, while summer temperatures can average up to 80 degrees Fahrenheit.

Statewide, average annual temperatures also vary greatly, thanks again to Illinois’ unique geography and location. In northeastern Illinois, Lake Michigan moderates the climate. The lake’s proximity causes cooler summers and warmer winters in the area. Southern Illinois, bordering Kentucky and Missouri, is generally about 10 degrees Fahrenheit warmer than the northern parts of the state that border Lake Michigan and Wisconsin. Now that we know where to look, we can find the five coldest places in Illinois that will chill you to your core.

Ranking the Coldest Places in Illinois

We ranked the coldest places in Illinois based on extensive climate statistics from Illinois State Climatologist climate station summaries for 186 stations across the state. These summaries include max, mean, and minimum temperatures “normals” for each station for all 12 months, as well as the annual 30-year average.

“According to the National Oceanic and Atmospheric Administration (NOAA), the 30-year average of a particular variable (e.g., temperature) is called the ‘normal,'” according to Illinois State Climatologist. “For example, the minimum temperature normal in January for a station in Chicago, Illinois, would be computed by taking the average of the 30 January values of monthly-averaged minimum temperatures from 1991 to 2020.”

Read the NOAA National Centers for Environmental Information Illinois State Climate Summary for 2022.

#1 Fulton, IL

Located in northwestern Illinois on the Mississippi River border with Iowa, Fulton, IL, has the lowest average annual maximum temperature of the state’s 186 climate stations at a chilly 55.5 degrees Fahrenheit. Its average minimum temperature is 39.1 degrees Fahrenheit. Fulton spends an average of 126.8 days annually with temperatures below freezing.

Like most places in the Northern Hemisphere, Fulton’s coldest month is January. For the first month of the year, Fulton’s average maximum temperature doesn’t rise above freezing at 25.5 degrees Fahrenheit. January’s minimum average is a bone-chilling 10.9 degrees Fahrenheit, with a mean temperature of 18.2 degrees Fahrenheit.

The city has a population of 3,647 people and sits within the limits of Whiteside County. Its record low of -33 degrees Fahrenheit will chill you to your core just thinking about it!

#2 Freeport, IL

Freeport is located about 40 miles south of Illinois’ border with Wisconsin. The area is prone to severe weather events, such as flooding from the nearby Pecatonica River. Freeport comes in as the second coldest place in Illinois with an average annual maximum temperature of just 56.2 degrees Fahrenheit. Its average minimum temperature for the year is 36.9 degrees Fahrenheit. Freeport spends an average of 152.7 days with temperatures below freezing each year.

January in Freeport averages 25.4 degrees Fahrenheit maximum. The month’s minimum average is a measly 9 degrees Fahrenheit, with a mean temperature of 17.2 degrees Fahrenheit. In 2006, its January low mean temperature was 4.1 degrees Fahrenheit.

Freeport has a population of 23,650 people and is the largest city in Stephenson County. On January 20, 1985, the city hit its record low of -27 degrees Fahrenheit.

#3 Paw Paw, IL

Paw Paw is a small village located in north central Illinois with a total area of 0.59 square miles. With an average annual maximum temperature of 56.5 degrees Fahrenheit, Paw Paw comes in as the third coldest place in Illinois. Its average yearly minimum temperature is 35.9 degrees Fahrenheit. More than 41 percent of the year is gripped by temperatures below 32 degrees Fahrenheit.

January in Paw Paw averages 25.3 degrees Fahrenheit maximum. The month’s minimum average is a shocking 7.7 degrees Fahrenheit, with a mean temperature of 16.5 degrees Fahrenheit. In 2006, its January low mean temperature was 6.2 degrees Fahrenheit.

Paw Paw has a population of 830 people as of the 2020 census. It is located in Lee County. On January 11, 1979, the town experienced a record low of -25 degrees Fahrenheit.

#4 Waukegan, IL

Situated about 26 miles north of Chicago, Waukegan is one of the Windy City’s industrial suburbs. Waukegan is Illinois’ fourth coldest city with an average annual maximum temperature of 56.7 degrees Fahrenheit. Its average minimum annual temperature is 37.9 degrees Fahrenheit. Residents of Waukegan brave freezing temperatures 141.5 days a year.

Maximum January temperatures in the suburb average 28.5 degrees Fahrenheit. Minimum temperatures in the first month of each year average 12 degrees Fahrenheit, with a mean temperature of 20.3. Waukegan saw its coldest mean temperature low in January of 1933 with 8.8 degrees Fahrenheit.

Waukegan has a population of 89,321, making it the seventh most populous city within the Chicago metropolitan area, and the 10th overall statewide. It is located in Lake County. The city of Waukegan set its record low of -27 degrees Fahrenheit on January 19, 1985.

#5 Lake Villa, IL

Located in northeastern Illinois near the state’s border with Wisconsin and Lake Michigan, Lake Villa‘s landscape is dominated by a group of glacial lakes known as the Chain O’Lakes. Out of the state’s 186 climate stations, this small town comes in as the fifth coldest place in Illinois. Its average annual maximum temperature is 56.7 degrees Fahrenheit, and its minimum is 38.5 degrees Fahrenheit. With 131.8 days spent below freezing temperatures, you could make ice cubes a little more than 35 percent of the year by setting your ice cube tray outside your back door.

January in Lake Villa doesn’t usually get warmer than 27.7 degrees Fahrenheit. The month’s minimum average temperature is 12.1 degrees Fahrenheit, with a mean temperature of 19.9 degrees Fahrenheit in January.

Lake Villa has a population of 8,741 people and shares Lake County with Waukegan.

Summary of Coldest Places in Illinois