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
January, noted for its average high-temperature of 26.8°F (-2.9°C) and an average low-temperature of 13.5°F (-10.3°C), is considered the coldest month.Humidity
With an average relative humidity of 84%, January is the most humid month.Rainfall
The month with the least rainfall is January, when the rain falls for 3.8 days and typically collects 0.87" (22mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. The month with the most snowfall is January, when snow falls for 9.8 days and typically aggregates up to 4.29" (109mm) 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 7:45 am and sunset at 4:56 pm. On the last day of January, sunrise is at 7:31 am and sunset at 5:30 pm CST.
Sunshine
January has the least sunshine of the year, with an average of 4.2h of sunshine.UV index
January, February, October through December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV radiation for average individuals.Note: The maximum UV index, 2 during January, leads to the following recommendations:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the coldest months?
How cold is January?
What is the most humid month?
What is the average humidity in January?
What is the driest month?
How many days does it rain in January?
What is the snowiest month?
How many days does it snow in January?
What is the average length of the day in January?
When is the sunrise / sunset in January?
What is the month with the least sunshine?
How many hours of sunshine does Jefferson have in January?
When is the lowest UV index in Jefferson?
What is the UV index intensity in January?
Average temperature in January
Jefferson, IA
- Average high temperature in January: 26.8°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (26.8°F).
- Average low temperature in January: 13.5°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (13.5°F).
Average pressure in January
Jefferson, IA
- 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 (29.88"Hg).
Average wind speed in January
Jefferson, IA
- Average wind speed in January: 10.6mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity in January
Jefferson, IA
- Average humidity in January: 84%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is October (69%).
Average rainfall in January
Jefferson, IA
- Average rainfall in January: 0.87"
The wettest month (with the highest rainfall) is May (4.06").
The driest month (with the least rainfall) is January (0.87").
Average rainfall days in January
Jefferson, IA
- Average rainfall days in January: 3.8 days
The month with the highest number of rainy days is June (17.3 days).
The month with the least rainy days is February (3.4 days).
Average snowfall in January
Jefferson, IA
- Average snowfall in January: 4.29"
The month with the highest snowfall is January (4.29").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in January
Jefferson, IA
- Average snowfall days in January: 9.8 days
The month with the highest number of snowfall days is January (9.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in January /
Average sunshine in January
Jefferson, IA
- 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: 4h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days in January
Jefferson, IA
- Average sunshine days in January: 18.1 days
The month with the most sunshine days is November (19.4 days).
The month with the least sunshine days is June (11.1 days).
Average UV index in January
Jefferson, IA
- Average UV index in January: 2
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, October, November and December (UV index 2).
Average cloud cover in January
Jefferson, IA
- Average cloud cover in January: 55
The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are July and September (Cloud cover 30).
Average visibility in January
Jefferson, IA
- 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).
Jefferson, Iowa, USA
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