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 brings the lowest temperatures, with an average high of 26.8°F (-2.9°C) and an average low of 13.5°F (-10.3°C).Humidity
The most humid month is January, with an average relative humidity of 84%.Rainfall
January is the month with the least rainfall. Rain falls for 3.8 days and accumulates 0.87" (22mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. The month with the most snowfall in Jefferson 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 in Jefferson 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 in Jefferson, with an average of 4.2h of sunshine.UV index
The months with the lowest UV index are January, February, October through December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a minimal health hazard from unsafe exposure to UV radiation for average individuals.Note: In January, a daily UV index of 2 turns into the following recommendations:
Extended sunlight exposure does not pose significant problems for most people, except for children, infants, and people with fair skin who always need shielding. Around midday, solar radiation is most harmful; hence, exposure should be limited. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Take precaution! The reflection from snow can almost double the UV radiation of the Sun.
Frequently asked questions
What time of the year is the coldest in Jefferson?
How cold is January in Jefferson?
What is the most humid month in Jefferson?
What is the average humidity in January in Jefferson?
What is the driest month in Jefferson?
How many days does it rain in January in Jefferson?
What is the snowiest month in Jefferson?
How much does it snow in Jefferson in January?
What is the average length of the day in January in Jefferson?
When are sunrise and sunset in January in Jefferson?
What is the month with the least sunshine in Jefferson?
How long on average sun shines in January in Jefferson?
What is the month with the lowest UV index in Jefferson?
How high is the UV index in January in Jefferson?
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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