January weather forecast
Rock City, IL

Today
Tomorrow
Long-term
YearJanuaryFMAMJJASOND
°Celsius°Fahrenheit
Share

Contents

Weather in January

January, the same as December, in Rock City, Illinois, is another subzero cold winter month, with an average temperature fluctuating between 25.2°F (-3.8°C) and 13.1°F (-10.5°C).

Temperature

Rock City's coldest weather arrives in January, when temperatures average a high of 25.2°F (-3.8°C) and a low of 13.1°F (-10.5°C).

Humidity

The most humid month in Rock City is January, with an average relative humidity of 87%.

Rainfall

In January, in Rock City, the rain falls for 4.9 days. Throughout January, 0.91" (23mm) of precipitation is accumulated. Throughout the year, in Rock City, there are 138 rainfall days, and 19.69" (500mm) of precipitation is accumulated.

Snowfall

January through April, October through December are months with snowfall. The month with the most snowfall in Rock City is January, when snow falls for 11.3 days and typically aggregates up to 2.99" (76mm) of snow.

Daylight

In Rock City, the average length of the day in January is 9h and 30min.
On the first day of January, sunrise is at 7:27 am and sunset at 4:35 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 5:09 pm CST.

Sunshine

January has the least sunshine of the year in Rock City, with an average of 3.6h of sunshine.

UV index

The months with the lowest UV index in Rock City, Illinois, are January and December, with an average maximum UV index of 1. 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 average daily UV index of 1 in January transforms into the following instructions:
Prolonged sun exposure should always be prevented in babies, children, and those with sensitive skin. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Be aware! The reflective nature of snow can magnify the Sun's UV radiation almost twofold.
[Resources]

Frequently asked questions

What month is the coldest in Rock City?

Rock City's coldest month, January, registers temperatures that range from a high of 25.2°F (-3.8°C) to a low of 13.1°F (-10.5°C).

How cold is it in Rock City in January?

The high-temperature, in January, in Rock City, is 25.2°F (-3.8°C), while the low-temperature averages to 13.1°F (-10.5°C).

What is the most humid month in Rock City?

The most humid month in Rock City, Illinois, is January, with an average relative humidity of 87%.

What is the average humidity in January in Rock City?

The average relative humidity in January in Rock City is 87%.

How much does it rain in Rock City in January?

In Rock City, in January, during 4.9 rainfall days, 0.91" (23mm) of precipitation is typically accumulated.

What is the snowiest month in Rock City?

The month with the most snowfall is January, when snow falls for 11.3 days and typically aggregates up to 2.99" (76mm) of snow.

How much does it snow in Rock City in January?

In Rock City, Illinois, in January, snow falls for 11.3 days, with typically accumulated 2.99" (76mm) of snow.

What is the average length of the day in January in Rock City?

In January, the average day length in Rock City is 9h and 30min.

What time are sunrise and sunset in January in Rock City?

On the first day of January in Rock City, sunrise is at 7:27 am and sunset at 4:35 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 5:09 pm CST.

What is the month with the least sunshine in Rock City?

January has the least sunshine of the year, with an average of 3.6h of sunshine.

How long on average sun shines in January in Rock City?

In January, the average sunshine duration in Rock City, Illinois, is 3.6h.

What are the months with the lowest UV index in Rock City?

January and December, with an average maximum UV index of 1, are months with the lowest UV index.

How high is the UV index in January in Rock City?

In January, the average daily maximum UV index in Rock City is 1. A UV Index of 2, and less, symbolizes a minimal hazard to health from unprotected exposure to UV radiation.
Today
Tomorrow
Long-term
YearJanuaryFMAMJJASOND
Dec
January
Feb
Average high temperature
32°F 0°C
25.2°F -3.8°C
29.5°F -1.4°C
Average low temperature
21.6°F -5.8°C
13.1°F -10.5°C
16.7°F -8.5°C
Average pressure
30.1" 765mmHg
30.12" 765mmHg
30.11" 765mmHg
Average wind speed
9.4mph 15.1km/h
9.8mph 15.8km/h
9.9mph 15.9km/h
Average max. wind speed
10.1mph 16.3km/h
10.5mph 16.9km/h
10.6mph 17.1km/h
Average wind speed gusts
15mph 24.1km/h
15.8mph 25.4km/h
16mph 25.7km/h
Average humidity
83%
87%
86%
Average rainfall
0.83" 21mm
0.91" 23mm
0.87" 22mm
Average rainfall days
6.8
4.9
5
Average snowfall
1.34" 34mm
2.99" 76mm
2.32" 59mm
Average snowfall days
8.2
11.3
10.7
Average daylight
9h 1min
9h 3min
10h 4min
Average sunshine
4h 0min
3h 4min
3h 5min
Average sunshine days
16.7
16.3
14.1
Average UV index
1
1
2
Average cloud cover
59%
63%
60%
Average visibility
6mi 9.7km
5mi 8km
5mi 8km

Average temperature in January
Rock City, IL

Average temperature in January - Rock City, IL
  • Average high temperature in January: 25.2°F

The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (25.2°F).

  • Average low temperature in January: 13.1°F

The month with the highest average low temperature is July (62.8°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).

[Resources]

Average pressure in January
Rock City, IL

Average pressure in January - Rock City, 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).

[Resources]

Average wind speed in January
Rock City, IL

Average wind speed in January - Rock City, IL
  • Average wind speed in January: 9.8mph

The windiest month (with the highest average wind speed) is April (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.5mph).

[Resources]

Average humidity in January
Rock City, IL

Average humidity in January - Rock City, 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%).

[Resources]

Average rainfall in January
Rock City, IL

Average rainfall in January - Rock City, IL
  • Average rainfall in January: 0.91"

The wettest month (with the highest rainfall) is June (2.87").
The driest month (with the least rainfall) is December (0.83").

[Resources]

Average rainfall days in January
Rock City, IL

Average rainfall days in January - Rock City, IL
  • Average rainfall days in January: 4.9 days

The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is January (4.9 days).

[Resources]

Average snowfall in January
Rock City, IL

Average snowfall in January - Rock City, IL
  • Average snowfall in January: 2.99"

The month with the highest snowfall is January (2.99").
The months with the least snowfall are May, June, July, August and September (0").

[Resources]

Average snowfall days in January
Rock City, IL

Average snowfall days in January - Rock City, IL
  • Average snowfall days in January: 11.3 days

The month with the highest number of snowfall days is January (11.3 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

[Resources]

Average daylight in January /
Average sunshine in January
Rock City, IL

Average daylight in January / Average sunshine in January - Rock City, 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 6min).

  • Average sunshine in January: 3h and 4min

The months with the most sunshine are July and August (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).

[Resources]

Average sunshine days in January
Rock City, IL

Average sunshine days in January - Rock City, IL
  • Average sunshine days in January: 16.3 days

The month with the most sunshine days is November (17.7 days).
The month with the least sunshine days is June (10.5 days).

[Resources]

Average UV index in January
Rock City, IL

Average UV index in January - Rock City, IL
  • Average UV index in January: 1

The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).

[Resources]

Average cloud cover in January
Rock City, IL

Average cloud cover in January - Rock City, IL
  • Average cloud cover in January: 63

The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is September (Cloud cover 32).

[Resources]

Average visibility in January
Rock City, IL

Average visibility in January - Rock City, IL
  • Average visibility in January: 5mi

The months with the highest visibility are March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, February, July and August (5mi).

[Resources]

Rock City, Illinois, USA

Weather forecast for today
Weather forecast for tomorrow
10 days weather forecast
Climate data
1January
2February
3March
4April
5May
6June
7July
8August
9September
10October
11November
12December

Weather forecast for your location

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