Chicago
Illinois, USA
Long-term weather forecast
Long-term weather forecast

October weather forecast and climate
Chicago, IL

An aerial view of the city of Chicago in Illinois, on the shores of Lake Michigan, with a superb view of the sandy beach of Oak Street
An aerial view of the city of Chicago in Illinois, on the shores of Lake Michigan, with a superb view of the sandy beach of Oak Street
October, like September, is another mild autumn month in Chicago, Illinois, with average temperature fluctuating between 59.5°F (15.3°C) and 48.9°F (9.4°C).

Temperature

In Chicago, the average high-temperature decreases, from an agreeable 71.1°F (21.7°C) in September, to a mild 59.5°F (15.3°C). The average low-temperature, is 48.9°F (9.4°C).

Humidity

October is the least humid month, with an average relative humidity of 73%.

Rainfall

In Chicago, in October, it is raining for 14.2 days, with typically 3.11" (79mm) of accumulated precipitation. Throughout the year, there are 160.2 rainfall days, and 36.97" (939mm) of precipitation is accumulated.

Snowfall

June through October are months without snowfall in Chicago.

Ocean temperature

In Chicago, Illinois, the average seawater temperature is 58.8°F (14.9°C).
Note: At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

Daylight

In October, the average length of the day in Chicago is 11.1h.

Sunshine

In Chicago, the average sunshine in October is 5.9h.

UV index

In October, the average daily maximum UV index in Chicago is 2. A UV Index estimate of 2, and below, represents a low health risk from unprotected exposure to the Sun's UV rays for ordinary individuals.
Note: The daily maximum UV index of 2 interpret into the following advice:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the temperature in October in Chicago?

In October, in Chicago, Illinois, the average high-temperature is 59.5°F (15.3°C), and the average low-temperature is 48.9°F (9.4°C).

What is the least humid month in Chicago?

October is the least humid month in Chicago, Illinois, with an average relative humidity of 73%.

What is the average humidity in October in Chicago?

In Chicago, Illinois, the average relative humidity in October is 73%.

How much does it rain in Chicago in October?

In Chicago, in October, it is raining for 14.2 days, with typically 3.11" (79mm) of accumulated precipitation.

Does it snow in Chicago in October?

In Chicago, in October, it doesn't snow. In November, it regularly snows.

When it does not snow in Chicago?

In Chicago, Illinois, snow does not fall in June through October.

What is the ocean temperature in October in Chicago?

In Chicago, in October, the average water temperature is 58.8°F (14.9°C). Swimming in 58.8°F (14.9°C) is considered life-threatening. Even a few minutes in 55.4°F (13°C) water is uncomfortable, and swimming below 50°F (10°C) may cause total loss of breathing control and cold shock, depending on a person's physique.

How many hours of daylight does Chicago have in October?

In Chicago, the average length of the day in October is 11.1h.

How many hours of sunshine does Chicago have in October?

The average sunshine in October in Chicago is 5.9h.

How high is the UV index in October in Chicago?

The average daily maximum UV index in October in Chicago, Illinois, is 2. A UV Index value of 2, and less, symbolizes a low health risk from unsafe exposure to the Sun's UV rays.
Average temperature in October - Chicago, IL
  • Average high temperature in October: 59.5°F

The warmest month (with the highest average high temperature) is August (77.5°F).
The month with the lowest average high temperature is January (29.7°F).

  • Average low temperature in October: 48.9°F

The month with the highest average low temperature is July (67.8°F).
The coldest month (with the lowest average low temperature) is January (20.7°F).

Average humidity in October - Chicago, IL
  • Average humidity in October: 73%

The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is October (73%).

Average rainfall in October - Chicago, IL
  • Average rainfall in October: 3.11"

The wettest month (with the highest rainfall) is June (4.88").
The driest month (with the lowest rainfall) is December (1.65").

Average rainfall days in October - Chicago, IL
  • Average rainfall days in October: 14.2 days

The month with the highest number of rainy days is July (18.5 days).
The month with the lowest number of rainy days is February (5.5 days).

Average snowfall in October - Chicago, IL
  • Average snowfall in October: 0"

The month with the highest snowfall is February (3.54").
Months with the lowest snowfall are June, July, August, September and October (0").

Average snowfall days in October - Chicago, IL
  • Average snowfall days in October: 0.2 days

The month with the highest number of snowfall days is January (10.6 days).
Months with the lowest number of snowfall days are June, July, August and September (0 days).

Average sea temperature in October - Chicago, IL
  • Average sea temperature in October: 58.9°F

The best month for swimming (with the highest average sea temperature) is August (73.9°F).
The coldest month (with the lowest average sea temperature) is February (36.9°F).

Average daylight in October / Average sunshine in October - Chicago, IL
  • Average daylight in October: 11.1h

The month with the longest days is June (Average daylight: 15.2h).
The month with shortest days is December (Average daylight: 9.2h).

  • Average sunshine in October: 5.9h

Months with most sunshine are July and August (Average sunshine: 10.6h).
The month with least sunshine is January (Average sunshine: 3.7h).

Average UV index in October - Chicago, IL
  • Average UV index in October: 2

Months with the highest UV index are July and August (UV index 6).
Months with the lowest UV index are January and December (UV index 1).