January weather forecast
Green Rock, IL

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Weather in January

January, like December, is a freezing cold winter month in Green Rock, Illinois, with an average temperature fluctuating between 15.4°F (-9.2°C) and 28.2°F (-2.1°C).

Temperature

With average high temperatures of 28.2°F (-2.1°C) and lows of 15.4°F (-9.2°C), January is the coldest month.

Humidity

January and July, with an average relative humidity of 83%, are the most humid months.

Rainfall

In Green Rock, during January, the rain falls for 3.2 days and regularly aggregates up to 0.43" (11mm) of precipitation. Throughout the year, there are 99.4 rainfall days, and 9.57" (243mm) of precipitation is accumulated.

Snowfall

January through April, September through December are months with snowfall. The month with the most snowfall is January, when snow falls for 7.2 days and typically aggregates up to 1.26" (32mm) of snow.

Daylight

In January, the average length of the day is 9h and 35min.
On the first day of January, sunrise is at 7:27 am and sunset at 4:42 pm. On the last day of the month, sunrise is at 7:14 am and sunset at 5:15 pm CST.

Sunshine

January has the least sunshine of the year, with an average of 3.9h of sunshine.

UV index

January is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a minimal health hazard from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: In January, a daily UV index of 1 turns into the following recommendations:
Infants, children, and people with sensitive skin should always have protection against lengthy periods of sun exposure. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Updated: Jul 22, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What part of the year is the coldest in Green Rock?

Green Rock's coldest month, January, registers temperatures that range from a high of 28.2°F (-2.1°C) to a low of 15.4°F (-9.2°C).

How cold is January?

In January, in Green Rock, the average high-temperature is 28.2°F (-2.1°C), and the average low-temperature is 15.4°F (-9.2°C).

What is the most humid month?

January and July, with an average relative humidity of 83%, are most humid months.

What is the average humidity in January in Green Rock?

The average relative humidity in January is 83%.

How much does it rain in January?

In Green Rock, in January, it is raining for 3.2 days, with typically 0.43" (11mm) of accumulated precipitation.

What is the snowiest month?

January is the month with the most snowfall. Snow falls for 7.2 days and accumulates 1.26" (32mm) of snow.

How much does it snow in January?

In January, it is snowing for 7.2 days. Throughout January, 1.26" (32mm) of snow is accumulated.

What is the average length of the day in January?

In Green Rock, the average day length in January is 9h and 35min.

When is the sunrise / sunset in January?

In January, on the first day of the month, sunrise is at 7:27 am and sunset at 4:42 pm. On the last day of the month, sunrise is at 7:14 am and sunset at 5:15 pm CST.

What is the month with the least sunshine?

The month with the least sunshine is January, with an average of 3.9h of sunshine.

How long on average sun shines in January?

In Green Rock, the average sunshine duration in January is 3.9h.

When is the lowest UV index in Green Rock?

With an average maximum UV index of 1, January is the month with the lowest UV index.

How high is the UV index in January?

The average daily maximum UV index in January is 1. A UV Index of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to Sun's UV rays.
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
Green Rock, IL

Average temperature in January - Green Rock, IL
  • Average high temperature in January: 28.2°F

The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28.2°F).

  • Average low temperature in January: 15.4°F

The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (15.4°F).

Average pressure in January
Green Rock, IL

Average pressure in January - Green Rock, IL
  • Average pressure in January: 30.13"Hg

The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).

Average wind speed in January
Green Rock, IL

Average wind speed in January - Green Rock, IL
  • Average wind speed in January: 10.3mph

The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.7mph).

Average humidity in January
Green Rock, IL

Average humidity in January - Green Rock, IL
  • Average humidity in January: 83%

The months with the highest relative humidity are January and July (83%).
The month with the lowest relative humidity is October (71%).

Average rainfall in January
Green Rock, IL

Average rainfall in January - Green Rock, IL
  • Average rainfall in January: 0.43"

The wettest month (with the highest rainfall) is May (1.61").
The driest month (with the least rainfall) is December (0.35").

Average rainfall days in January
Green Rock, IL

Average rainfall days in January - Green Rock, IL
  • Average rainfall days in January: 3.2 days

The month with the highest number of rainy days is May (13.4 days).
The month with the least rainy days is January (3.2 days).

Average snowfall in January
Green Rock, IL

Average snowfall in January - Green Rock, IL
  • Average snowfall in January: 1.26"

The month with the highest snowfall is January (1.26").
The months with the least snowfall are May, June, July and August (0").

Average snowfall days in January
Green Rock, IL

Average snowfall days in January - Green Rock, IL
  • Average snowfall days in January: 7.2 days

The month with the highest number of snowfall days is January (7.2 days).
The months with the least snowfall days are May, June, July and August (0 days).

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

Average daylight in January / Average sunshine in January - Green Rock, IL
  • Average daylight in January: 9h and 4min

The month with the longest days is June (Average daylight: 15h and 6min).
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 July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).

Average sunshine days in January
Green Rock, IL

Average sunshine days in January - Green Rock, IL
  • Average sunshine days in January: 22.2 days

The month with the most sunshine days is December (22.4 days).
The month with the least sunshine days is June (14.4 days).

Average UV index in January
Green Rock, IL

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

The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is January (UV index 1).

Average cloud cover in January
Green Rock, IL

Average cloud cover in January - Green Rock, IL
  • Average cloud cover in January: 58

The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 30).

Average visibility in January
Green Rock, IL

Average visibility in January - Green Rock, 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).

Green Rock, Illinois, USA

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