January weather forecast
Lake Forest, IL

Share

Weather in January

January, the same as December, in Lake Forest, Illinois, is another subzero cold winter month, with temperature in the range of an average low of 18.9°F (-7.3°C) and an average high of 28.6°F (-1.9°C).

Temperature

With average high temperatures of 28.6°F (-1.9°C) and lows of 18.9°F (-7.3°C), January is the coldest month.

Humidity

January and February, with an average relative humidity of 82%, are the most humid months.

Rainfall

In Lake Forest, in January, it is raining for 6.2 days, with typically 1.54" (39mm) of accumulated precipitation. Throughout the year, there are 154.1 rainfall days, and 30.24" (768mm) of precipitation is accumulated.

Snowfall

Months with snowfall in Lake Forest are January through April, October through December. January is the month with the most snowfall in Lake Forest, Illinois. Snow falls for 11.9 days and accumulates 4.13" (105mm) of snow.

Daylight

In January, the average length of the day is 9h and 31min.
On the first day of the month, sunrise is at 7:20 am and sunset at 4:29 pm. On the last day of January, sunrise is at 7:05 am and sunset at 5:03 pm CST.

Sunshine

January has the least sunshine of the year in Lake Forest, with an average of 3.8h of sunshine.

UV index

In January, the average daily maximum UV index is 2. A UV Index value of 2, and less, symbolizes a low health risk from unsafe exposure to UV radiation for the ordinary person.
Note: The maximum UV index, 2 during January, leads to the following recommendations:
Prolonged sun exposure should always be prevented in babies, children, and those with sensitive skin. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Enhance your sun protection with tightly woven, yet airy clothing. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What month is the coldest in Lake Forest?

Lake Forest's January weather, with an average high temperature of 28.6°F (-1.9°C) and an average low temperature of 18.9°F (-7.3°C), tends to be the coldest of the year.

How cold is it in Lake Forest in January?

The high-temperature, in January, in Lake Forest, records 28.6°F (-1.9°C), while the low-temperature is 18.9°F (-7.3°C).

What are the most humid months in Lake Forest?

January and February, with an average relative humidity of 82%, are most humid months in Lake Forest, Illinois.

What is the average humidity in January in Lake Forest?

The average relative humidity in January in Lake Forest is 82%.

How much does it rain in Lake Forest in January?

In Lake Forest, Illinois, in January, it is raining for 6.2 days, with typically 1.54" (39mm) of accumulated precipitation.

What is the snowiest month in Lake Forest?

January is the month with the most snowfall. Snow falls for 11.9 days and accumulates 4.13" (105mm) of snow.

How much does it snow in Lake Forest in January?

In Lake Forest, during January, snow falls for 11.9 days and regularly aggregates up to 4.13" (105mm) of snow.

What is the average length of the day in January in Lake Forest?

In Lake Forest, Illinois, the average day length in January is 9h and 31min.

What time are sunrise and sunset in January in Lake Forest?

On the first day of January in Lake Forest, sunrise is at 7:20 am and sunset at 4:29 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 5:03 pm CST.

What is the month with the least sunshine in Lake Forest?

January has the least sunshine of the year in Lake Forest, with an average of 3.8h of sunshine.

How many hours of sunshine does Lake Forest have in January?

In January, the average sunshine duration in Lake Forest, Illinois, is 3.8h.

How high is the UV index in January in Lake Forest?

The average daily maximum UV index in January in Lake Forest is 2. A UV Index estimate of 2, and below, represents a minimal hazard to health from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in January
Lake Forest, IL

Average temperature in January - Lake Forest, IL
  • Average high temperature in January: 28.6°F

The warmest month (with the highest average high temperature) is July (77.7°F).
The month with the lowest average high temperature is January (28.6°F).

  • Average low temperature in January: 18.9°F

The months with the highest average low temperature are July and August (66.7°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).

Average pressure in January
Lake Forest, IL

Average pressure in January - Lake Forest, IL
  • Average pressure in January: 30.1"Hg

The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

Average wind speed in January
Lake Forest, IL

Average wind speed in January - Lake Forest, IL
  • Average wind speed in January: 11.9mph

The windiest month (with the highest average wind speed) is January (11.9mph).
The calmest month (with the lowest average wind speed) is August (7.4mph).

Average humidity in January
Lake Forest, IL

Average humidity in January - Lake Forest, IL
  • Average humidity in January: 82%

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

Average rainfall in January
Lake Forest, IL

Average rainfall in January - Lake Forest, IL
  • Average rainfall in January: 1.54"

The wettest months (with the highest rainfall) are May and June (3.82").
The driest month (with the least rainfall) is December (1.3").

Average rainfall days in January
Lake Forest, IL

Average rainfall days in January - Lake Forest, IL
  • Average rainfall days in January: 6.2 days

The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (5.9 days).

Average snowfall in January
Lake Forest, IL

Average snowfall in January - Lake Forest, IL
  • Average snowfall in January: 4.13"

The month with the highest snowfall is January (4.13").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in January
Lake Forest, IL

Average snowfall days in January - Lake Forest, IL
  • Average snowfall days in January: 11.9 days

The month with the highest number of snowfall days is January (11.9 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in January /
Average sunshine in January
Lake Forest, IL

Average daylight in January / Average sunshine in January - Lake Forest, IL
  • Average daylight in January: 9h and 3min

The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).

  • Average sunshine in January: 3h and 5min

The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).

Average sunshine days in January
Lake Forest, IL

Average sunshine days in January - Lake Forest, IL
  • Average sunshine days in January: 12.8 days

The month with the most sunshine days is December (15.3 days).
The month with the least sunshine days is April (10.8 days).

Average UV index in January
Lake Forest, IL

Average UV index in January - Lake Forest, IL
  • Average UV index in January: 2

The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).

Average cloud cover in January
Lake Forest, IL

Average cloud cover in January - Lake Forest, IL
  • Average cloud cover in January: 61

The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are July and August (Cloud cover 27).

Average visibility in January
Lake Forest, IL

Average visibility in January - Lake Forest, IL
  • Average visibility in January: 6mi

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

Lake Forest, Illinois, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location