If you’re interested in visiting the windy city, it will be important to consider what kind of weather you can expect during your trip.
This post provides details about what the weather is like each month, as well as tips on the warmest and coldest months of the year in Chicago.
Chicago Weather by Month
This section will include some of the most important information about what kind of weather to expect throughout each month of the year, including tips about the average temperatures and snowfall.
Weather in January
The coldest and snowiest month of the year is often January.
With an average high of 31 °F (-1 °C), the temperatures range from 26 °F to 36 °F (-3 – 2 °C).
The average low temperature this month is 17 °F (-9 °C).
The number of days with rain or new snowfall ranges from 8 to 11, with the likelihood of snowfall decreasing during the month.
Check our full post covering the weather in Chicago during January.
Weather in February
The average high temperature in February is 35 °F (2 °C), with temperatures ranging from 30 °F to 40 °F (-1 - 5 °C). The average low temperature this month is 20 °F (-7 °C).
Despite this, the temperature continues to rise during this brief month.
By the end of February, it will likely rise by roughly 9°F (5 °C), with an average of three days reaching the 50s °F (over 10 °C).
On average, there are six days with no clouds and seven or so days when it rains.
Cloudy or snowy weather will prevail for the remainder of the month.
Check our full post covering the weather in Chicago during February.
Weather in March
Chicago experiences a chilly start to March, with overnight lows predicted in the mid-20s F. (-4C to -3C).
Some of the icier mornings may get as low as 15 F (-9C) or even below.
Early in the month, daytime highs will often be cool, averaging around 40 F. (4-5C).
However, as the month goes on, the days quickly warm up.
By the end of the month, it's more likely that morning lows will be in the mid-30s F (1-2C) and afternoon highs will be in the low to mid-50s F. (11-12C).
On around 11 days of the month, some precipitation is expected; however, only 1 or 2 days will experience considerable precipitation of at least 1/2 inch (13mm).
Check our full post covering the weather in Chicago during March.
Weather in April
After the long winter, the weather in April is typically lovely.
You'll want to be ready for the weather so that you can pack appropriately, and so that nothing will prevent you from enjoying your visit to the city.
With an average high of 59 °F (15 °C), the temperatures range from 55 °F to 63 °F (13-17 °C).
On the other hand, this month's typical low temperature is 39 °F (4 °C).
This month, the temperatures tend to rapidly warm up, and by the end of April, they have usually increased by 12°F (7°C).
Most days will achieve a high temperature of over 40 °F (4 °C), and approximately half of the days this month will even get above 60 °F (about 15 °C).
Check our full post covering the weather in Chicago during April.
Weather in May
With an average high of 70 °F (21 °C), the temperatures range from 66 °F to 74 °F (19-23 °C).
On the other hand, this month's typical low temperature is just 48 °F (9 °C).
Through the course of the month, there is a steady increase in temperature; by the end of May, it is 10 °F (5 °C) warmer.
Over the course of 12 wet days, the city typically receives 3.7 inches (93 mm) of rain during this month.
With an average of 7 clear days, the sun shines for 58% of the day.
Check our full post covering the weather in Chicago during May.
Weather in June
In general, Chicago experiences moderate daytime temperatures with warm afternoons, especially in the second half of the month.
Early in the month, afternoon highs are typically in the mid-70s F (23 C), rising toward the end of the month to the low 80s F (28 C).
Early in June, lows at night and in the morning are often in the mid to high 50s F (13-15C), increasing to the mid-60s F (17-19C) by the end of the month.
This month, there should be roughly 20 days that are at least partially sunny.
Check our full post covering the weather in Chicago during June.
Weather in July
Chicago experiences warm afternoons and nights in July, with generally pleasant mornings.
On most days, afternoon high temperatures range from the lower 80s F (27–28 C) to the lower 90s F. (32-33 C).
Early in the month, low temperatures for late at night and early in the morning are often in the upper 60s F (about 20 C), increasing to the lower 70s F (21–22 C) by the end of the month.
This month, there will be sunshine or partly sunny skies for about 21 days.
Check our full post covering the weather in Chicago during July.
Weather in August
In Chicago, August is typically characterized by warm afternoons and early evenings, as well as generally agreeable mornings and evenings.
Early in the month, daytime highs will typically range from the low 80s F (27–28 C) to the upper 70s F (approximately 26 C) by the end of the month.
Overnight and early morning low temperatures in August typically range from the mid to upper 60s F (19–20 C) early in the month to the low 70s F (21–22 C) by the end of the month.
On average, August will have 20 days with bright or partly sunny skies. 9 to 10 days get some rain, but only 2 to 3 days see heavy showers of at least 0.5 inches (13 mm).
Check our full post covering the weather in Chicago during August.
Weather in September
In terms of temperatures, this month turns out to be fairly nice, with fewer days of rain than in August.
The long summer days are now in the past.
In Chicago, the temperature frequently exceeds 60 °F (16 °C), with an average high of 75 °F (24 °C) and low of 54 °F (12 °C).
After the summer thunderstorms of August, there is a sharp reduction in storm activity, and rainfall only totals 3.2 inches (82 mm) over the period of around 8 rainy days.
Check our full post covering the weather in Chicago during September.
Weather in October
Due to the fact that fall is now in full swing, Chicago's weather can alter throughout the month of October.
Early in the month, afternoon highs are still comfortable, rising to the upper 60s F (about 20C), with overnight and early morning lows falling into the upper 40s F. (about 9C).
By the end of the month, morning lows will be close to 40 F (about 4C) and afternoon highs will be in the mid-to upper-50s F range (13 to 14C).
This month, rain typically falls on 8 to 9 days, however major rainfalls of 0.5 inches (or 13 mm) or more often only happen on 2 days.
Check our full post covering the weather in Chicago during October.
Weather in November
By the end of November, Chicago's temperature has frequently dropped 15 °F (9 °C) from where it started as the city continues to cool during this month.
With an average high of 48 °F (9 °C), the temperatures range from 44 °F to 53 °F (7-11 °C).
On the other hand, this month's average low is 32 °F (0 °C), with a few days still below freezing.
Rain or snow, the city typically receives 3.2 inches (80 mm) of precipitation during this month.
Check our full post covering the weather in Chicago during November.
Weather in December
Chicago's Decembers are typically very chilly and frequently below freezing.
On average, 26 days a year see temperatures drop below freezing, with 1-2 of those days seeing temperatures as low as 0 F (-18 C).
Daytime highs at the beginning of the month typically range from the low to mid-40s F (5 to 6 C), with a few of the warmer afternoons reaching as high as the mid-50s F. (12C to 13C).
However, afternoon temperatures are more likely to be in the low to mid-30s F towards the end of this month (0C to 1C).
Early in the month, low temperatures at night and in the morning in December typically range from the low to mid-30s F (approximately 1C).
By the end of the month, temperatures are more likely to be in the low to mid-20s F (-6 to -4C), although a few of the colder mornings may only reach single digits F (-22 to -19C) or below.
This month, there are about 11 days with measurable precipitation, with 1 day typically recording 0.5 inches (about 13 mm) or more.
Check our full post covering the weather in Chicago during December.
What is the Coldest Month in Chicago?
With an average of 16 days each month below freezing and only one day rising above 50 °F (10 °C), January is usually the coldest month of the year.
In comparison, while the temperatures dip below freezing on around 26 days in December, it’s less likely to stay cold throughout the day.
By the time February arrives, temperatures range from 30 to 40 degrees Fahrenheit (-1 to 5 degrees Celsius), with an average high of 35 degrees Fahrenheit (2 degrees Celsius), but nighttime lows below freezing are still common.
When Does it Snow in Chicago?
You can usually expect snowfall in Chicago from December - February and sometimes during shoulder months as well.
January brings an average of 10.8 inches (27.4 mm) of snow, while February will typically have around 9.1 inches (23.1 cm) of white stuff.
There are usually about 8-12 days of rain or snowfall during each of these months.
What is the Warmest Month in Chicago?
July is almost always the hottest month to visit Chicago.
This month, roughly 6 days will have highs of 90 F (about 32 C) or more. Chicago's July record high temperature is 104 F. (40.0 C).
July in Chicago can be a bit humid, with 11–15 days classified as muggy and 3–6 of these days as oppressive.
In the early part of August, when around half the days would be considered muggy, it can still be quite humid.
However, only around 1 in 3 days will be muggy by the end of the month.
There are typically only around 4 days in August when temperatures reach or exceed 90 F (32 C).