Contents
- Weather in January
- Frequently asked questions
- Average temperature in January
- Average pressure in January
- Average wind speed in January
- Average humidity in January
- Average rainfall in January
- Average rainfall days in January
- Average snowfall in January
- Average snowfall days in January
- Average daylight in January
- Average sunshine in January
- Average sunshine days in January
- Average UV index in January
- Average cloud cover in January
- Average visibility in January
Weather in January
Temperature
Alton's coldest weather arrives in January, when temperatures average a high of 36.1°F (2.3°C) and a low of 23.2°F (-4.9°C).Humidity
In Alton, the average relative humidity in January is 77%.Rainfall
In Alton, in January, it is raining for 5.7 days, with typically 0.94" (24mm) of accumulated precipitation. In Alton, during the entire year, the rain falls for 128.3 days and collects up to 18.9" (480mm) of precipitation.Snowfall
January through March, November and December are months with snowfall. In Alton, during January, snow falls for 5.4 days and regularly aggregates up to 1.06" (27mm) of snow. Throughout the year, there are 17.9 snowfall days, and 3.58" (91mm) of snow is accumulated.Daylight
In Alton, the average length of the day in January is 9h and 49min.On the first day of the month, sunrise is at 7:19 am and sunset at 4:49 pm. On the last day of January, sunrise is at 7:07 am and sunset at 5:20 pm CST.
Sunshine
The months with the least sunshine are January and February, with an average of 4.5h of sunshine.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: A daily high UV index of 2 in January leads to these guidelines:
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. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days. Take warning! The intensity of the Sun's UV radiation can be nearly amplified twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What part of the year is the coldest in Alton?
How cold is it in Alton in January?
What is the average humidity in January in Alton?
How much does it rain in Alton in January?
How many days does it snow in January in Alton?
What is the average length of the day in January in Alton?
What time are sunrise and sunset in January in Alton?
What are the months with the least sunshine in Alton?
How many hours of sunshine does Alton have in January?
What is the month with the lowest UV index in Alton?
What is the UV index intensity in January in Alton?
Average temperature in January
Alton, IL
- Average high temperature in January: 36.1°F
The warmest month (with the highest average high temperature) is July (85.3°F).
The month with the lowest average high temperature is January (36.1°F).
- Average low temperature in January: 23.2°F
The month with the highest average low temperature is July (67.6°F).
The coldest month (with the lowest average low temperature) is January (23.2°F).
Average pressure in January
Alton, IL
- Average pressure in January: 30.16"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in January
Alton, IL
- Average wind speed in January: 9.6mph
The windiest month (with the highest average wind speed) is January (9.6mph).
The calmest month (with the lowest average wind speed) is July (5.7mph).
Average humidity in January
Alton, IL
- Average humidity in January: 77%
The month with the highest relative humidity is July (80%).
The month with the lowest relative humidity is October (71%).
Average rainfall in January
Alton, IL
- Average rainfall in January: 0.94"
The wettest month (with the highest rainfall) is May (2.44").
The driest month (with the least rainfall) is February (0.83").
Average rainfall days in January
Alton, IL
- Average rainfall days in January: 5.7 days
The month with the highest number of rainy days is July (15.4 days).
The month with the least rainy days is January (5.7 days).
Average snowfall in January
Alton, IL
- Average snowfall in January: 1.06"
The month with the highest snowfall is February (1.14").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in January
Alton, IL
- Average snowfall days in January: 5.4 days
The month with the highest number of snowfall days is January (5.4 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
Alton, IL
- Average daylight in January: 9h and 5min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in January: 4h and 3min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 30min).
Average sunshine days in January
Alton, IL
- Average sunshine days in January: 20.9 days
The month with the most sunshine days is December (21 days).
The month with the least sunshine days is June (12.6 days).
Average UV index in January
Alton, IL
- Average UV index in January: 2
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in January
Alton, IL
- Average cloud cover in January: 52
The month with the most cloud cover is January (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in January
Alton, 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).
Alton, Illinois, USA
Weather forecast for your location
2. Allow the app to use your location