January weather forecastLanark, IL
January
Weather in January
Transitioning from the ending month, December, to January, there is a noticeable dip in the temperature, that marks the winter season in Lanark, Illinois, USA. The mercury usually silhouettes around 13.5°F (-10.3°C) to 25.9°F (-3.4°C), appending this period a rather icy exterior. Humidity takes a crest, touching 87%, an attribute often linked with winter months. The city enters its peak snowfall period, with snow-covered lanes and roofs becoming a common sight. Irrespective of the colder season, days are still decently bright with around 9.5hours of daylight.Temperature
January, with average temperatures reaching a high of 25.9°F (-3.4°C) and a low of 13.5°F (-10.3°C), is the coldest month.Humidity
January is the most humid month, with an average relative humidity of 87%.Rainfall
January and February are months with the least rain when the rain falls for 4.8 days and typically aggregates up to 0.71" (18mm) of rain.Snowfall
January through April, October through December are months with snowfall. The month with the most snowfall is January, when snow falls for 11.2 days and typically aggregates up to 2.64" (67mm) of snow.Daylight
In January, the average length of the day is 9h and 32min.On the first day of the month, sunrise is at 7:27 am and sunset at 4:37 pm. On the last day of January, in Lanark, sunrise is at 7:13 am and sunset at 5:12 pm CST.
Sunshine
January has the least sunshine of the year, with an average of 3.7h of sunshine.UV index
The months with the lowest UV index are January and December, with an average maximum UV index of 1. A UV Index estimate of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV radiation for the average person.Note: A maximum daily UV index of 1 during January morphs into the following directions:
While most can endure approximately an hour in the sun without burning, children always require protection from sunlight. Exposing oneself to the midday Sun can be harmful due to the strong UV radiation; limit your time outside. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation. Warning! The reflection from snow can nearly magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Lanark, IL
- Average high temperature in January: 25.9°F
The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (25.9°F).
- Average low temperature in January: 13.5°F
The month with the highest average low temperature is July (63.3°F).
The coldest month (with the lowest average low temperature) is January (13.5°F).
Average pressure in January
Lanark, IL
- Average pressure in January: 30.12"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in January
Lanark, IL
- Average wind speed in January: 9.8mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.5mph).
Average humidity in January
Lanark, IL
- Average humidity in January: 87%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (75%).
Average rainfall in January
Lanark, IL
- Average rainfall in January: 0.71"
The wettest month (with the highest rainfall) is May (2.76").
The driest months (with the least rainfall) are January and February (0.71").
Average rainfall days in January
Lanark, IL
- Average rainfall days in January: 4.8 days
The month with the highest number of rainy days is May (17.9 days).
The month with the least rainy days is February (4.4 days).
Average snowfall in January
Lanark, IL
- Average snowfall in January: 2.64"
The month with the highest snowfall is January (2.64").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in January
Lanark, IL
- Average snowfall days in January: 11.2 days
The month with the highest number of snowfall days is January (11.2 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
Lanark, IL
- Average daylight in January: 9h and 30min
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 42min
The month with the most sunshine is July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in January
Lanark, IL
- Average sunshine days in January: 17.3 days
The month with the most sunshine days is November (19.7 days).
The month with the least sunshine days is June (10 days).
Average UV index in January
Lanark, IL
- Average UV index in January: 1
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in January
Lanark, IL
- Average cloud cover in January: 61
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in January
Lanark, IL
- Average visibility in January: 5mi
The months with the highest visibility are February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, July and August (5mi).





