According to Abbreviation Finder, Illinois is one of the northern states of the United States of America. With nearly 13 million inhabitants, Illinois is one of the most populous states in the country. Illinois is also one of the top performers in the US in economic terms. The state owes this mainly to the large penetration of industrial areas and the presence of many agricultural companies. A number of raw materials are also widely represented, such as petroleum, coal and wood. The landscape is mainly hilly, with a highest point of only 376 meters above sea level. Illinois is not located on a sea or ocean, but on the large Lake Michigan. This lake is also home to Illinois’ largest city, Chicago.
Illinois has a warm continental climate, with the weather pattern being much more erratic than the statistics suggest. The long-term average climate figures are no longer a guideline, with very large fluctuations possible. For example, it can get seriously cold in winter, with moderate to sometimes severe frost during the day, and in summer it can be far above the average temperature of 29-32 degrees Celsius. Illinois falls within Tornado Alley, a large area in the US where vortices (tornadoes) can occur. On average, about 35 tornadoes occur in Illinois each year. While Illinois isn’t above average in tornado numbers and tornado strength, the average damage here is greater than many other places.
Climate figures
The figures below are based on long-term average climate statistics. The temperatures are displayed in degrees Celsius (°C).
| maximum temperature | minimum temperature | hours of sunshine per day | days of rainfall per month | water temperature | |
| January | 1℃ | -10℃ | 5 | 9 | 4℃ |
| February | 3℃ | -7℃ | 6 | 9 | 3℃ |
| March | 11℃ | -1℃ | 6 | 12 | 2℃ |
| April | 18℃ | 6℃ | 8 | 11 | 3℃ |
| May | 24℃ | 11℃ | 9 | 11 | 5℃ |
| June | 29℃ | 16℃ | 10 | 9 | 11℃ |
| July | 31℃ | 19℃ | 10 | 9 | 19℃ |
| August | 29℃ | 17℃ | 9 | 8 | 21℃ |
| September | 26℃ | 13℃ | 8 | 9 | 20℃ |
| October | 20℃ | 7℃ | 7 | 8 | 15℃ |
| November | 11℃ | 1℃ | 5 | 10 | 9℃ |
| December | 3℃ | -6℃ | 4 | 10 | 6℃ |
The climate of Belleville
Belleville is a small town in southwestern Illinois, not far from the Mississippi. Belleville is located in St. Clair County. The city originated in the early 19th century and grew in size in the middle of that century. It was mainly the Germans who moved to this part of America. During this period almost the entire population of Belleville was made up of Germans. There are still houses in the town in the typical German style. The German Oktoberfest is still exuberantly celebrated here.
Belleville has a warm continental climate, which is less cold than most places in Illinois due to the southern location of the city. The nights are still very cold during the winter period, with temperatures that can dip well below freezing. The summer period in Belleville is very pleasant, with temperatures averaging around 30 degrees Celsius. Precipitation is fairly evenly distributed throughout the year. During tornado season you have a chance of tornadoes.
The climate of Bloomington
According to Countryaah, Bloomington is a medium-sized city in the central part of the US state of Illinois. Bloomington is located in McLean County. The Bloomington town of Normal is also located in this county. The Kickapoo Indians originally lived in this area. The first Europeans came here at the beginning of the 19th century. The Illinois State University is located here. The city is nationally known for its golf courses. The golf courses that surround the Bloomington-Normal metropolitan area are among the finest in the United States.
Bloomington has a warm continental climate, with a particularly cold winter period. During the coldest winter months, the mercury struggles to rise above freezing. The summer months, on the other hand, are warm and sometimes even hot. During the hottest days of the year, the mercury can easily rise to 36 degrees Celsius. Precipitation is evenly distributed throughout the year and can come down as snow or sleet during the winter.
The climate of Champaign
Champaign is a medium-sized city in the western central part of the US state of Illinois. The city is a sister city of Urbana and was created in the mid-19th century when a train station was built here. Today the city is a major student city and the University of Illinois at Urbana–Champaign is the city’s largest employer. Champaign is served by the Willard Airport.
Champaign has a warm continental climate, which is characterized by the warm summer months and the cold winter period. During the coldest winter months, the mercury here hardly rises above freezing. Precipitation is fairly evenly distributed throughout the year, but peaks during the early summer months. On average, Champaign has slightly more days of precipitation than other places in Illinois. You have to take tornadoes into account here.
The climate of Chicago
Chicago is a large city in the northeast of the state of Illinois, on Lake Michigan. The nickname of the city is “The windy city”. It is the third largest city in the US after Los Angeles and New York: more than 9 million people live in the Chicago metropolitan area. The Chicago River runs through the city, whose natural flow has been artificially reversed. During St. Patrick’s Day, this river is colored green. The city is home to many major sports teams, such as the Chicago Bulls, the Chicago White Sox and the Chicago Bears, among many others. Chicago is known for its education: there are many universities here, of which Northwestern University, the University of Chicago and the University of Illinois at Chicago are the best known. There are two major airports near the city, Midway International Airport and O’Hare International Airport. Chicago is one of the largest rail hubs in the world.
Chicago has a warm continental climate, influenced by Lake Michigan. Winters are particularly cold and during some months of the year the mercury struggles to rise above freezing. During the summer months it can get quite warm again, with average temperatures just below 30 degrees Celsius. Due to the presence of Lake Michigan, temperatures here are generally slightly lower than in the more inland places. Average precipitation is fairly evenly distributed throughout the year, but will often come down as snow in the winter months.
The climate of Decatur
Decatur is a large city in the central part of the US state of Illinois. The city is located on the Sangamon River and on Lake Decatur in Macon County. The city is struggling with a declining population. This is mainly due to the disappearance of a number of large employers from the city. Partly because of this, the crime rates here are higher than in most smaller cities in America. The Lincoln Trail Homestead State Memorial is located in the city.
Decatur has a warm continental climate, with high rainfall throughout the year. Because the city is located in the so-called Tornado Alley, you have to take tornadoes into account. The winter period is very cold here, especially during the nights. During the nights, the mercury can drop well below freezing. The summer months are warm and sometimes even hot, with temperatures reaching up to 36 degrees Celsius.
The climate of Moline
Moline is a small town in northwestern Illinois, in Rock Island County. The city is located on the Mississippi River, which forms the border with the state of Iowa. The first inhabitants of this area were the Sauk and Meskwaki Indians. The first Europeans did not arrive until the middle of the 19th century. Today Moline is an important trading town. The city’s largest employer is Deere & Company, better known as John Deere.
Moline has a warm continental climate, with cold winter months and a short, warm summer period. Due to the city’s northern location, average temperatures in Moline are slightly lower than in other parts of the state of Illinois. The winter months are characterized by a long period of frost. The nights are especially cold during this period. Summers are pleasantly warm and sometimes even hot. The most precipitation falls on average during this period.
The climate of Peoria
Peoria is a large city in the northwestern/central part of the state of Illinois. Peoria was founded in the latter part of the 17th century, making it the oldest city in Illinois. The city is named after the Peoria tribe, who originally lived in this area. The city is served by the General Wayne Downing Peoria International Airport and several rail lines. The city is also located on several major highways.
Peoria has a warm continental climate, with cold winters and hot summer months. On average, Peoria receives almost 1000 millimeters of precipitation on an annual basis. During the winter months, this precipitation will mainly consist of snow and sleet. In the months of December and January the mercury hardly rises above the freezing point. The city is located in Tornado Alley, an area that covers much of the United States. During the tornado season you have to take tornadoes into account here.
The climate of Quincy
Quincy is a small city in the western US state of Illinois. The city is located on the Mississippi River, which forms the border with the state of Missouri. During the spring, the high rainfall can cause the river to overflow, which can cause major problems in the city. Quincy is located in the original habitat of the Sauk, Fox and Kickapoo Indian tribes.
Quincy has a warm continental climate, with a big difference between the summer and winter months. During the summer months it can get very hot here and temperatures well above 30 degrees Celsius are no exception. The winter months, on the other hand, are cold, with long periods of night frost. During the coldest winter months, the mercury struggles to rise above freezing. Precipitation is fairly evenly distributed throughout the year. During the winter months there is on average slightly less precipitation. This precipitation will mainly consist of snow and sleet.
The climate of Springfield
Not the metropolis of Chicago, but Springfield, centrally located in Illinois, is the capital of this northern state. Former President Abraham Lincoln once started his political career in this nearly two-century-old city. Springfield has more than 100,000 inhabitants. The city has the grid pattern that is so characteristic of many American cities.
Springfield has a warm continental climate (type Dfa according to the Köppen climate classification), with winters that are on the cool side, a short and warm spring, warm summers and unpredictable autumn days. In total, the sun shines a little less than 2700 hours a year and there is about nine hundred millimeters of precipitation. In winter, part of the precipitation falls in the form of snow. On average it snows for about twenty days, which in total is good for a snow cover of 60 to 65 centimeters. These are averages from which large deviations are possible due to the erratic climate. Some winters there is more than a meter of snow and occasionally there is a winter where there is no significant snow.
