January weather forecastThornton, CO
January
Weather in January
January, like December, in Thornton, Colorado, is another cold winter month, with an average temperature ranging between min 23.2°F (-4.9°C) and max 42.4°F (5.8°C).Temperature
Shifting into January, Thornton records an average high-temperature of a still cold 42.4°F (5.8°C), presenting minor fluctuations compared to the previous month. Throughout January, the average low-temperature dips to a freezing cold 23.2°F (-4.9°C).Humidity
In Thornton, the average relative humidity in January is 62%.Rainfall
January and December are months with the least rain when the rain falls for 2.3 days and typically aggregates up to 0.08" (2mm) of rain.Snowfall
Months with snowfall are January through May, October through December. In Thornton, Colorado, during January, snow falls for 3.2 days and regularly aggregates up to 0.71" (18mm) of snow. Throughout the year, there are 19.6 snowfall days, and 8.5" (216mm) of snow is accumulated.Daylight
In Thornton, the average length of the day in January is 9h and 44min.On the first day of January in Thornton, sunrise is at 7:21 am and sunset at 4:45 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 5:17 pm MST.
Sunshine
In Thornton, the average sunshine in January is 7h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index of 2 during January translates into these guidelines:
It is important to always shield children, babies, and individuals with sensitive skin from prolonged exposure to the sun. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Thornton, CO
- Average high temperature in January: 42.4°F
The warmest month (with the highest average high temperature) is July (88.3°F).
The month with the lowest average high temperature is December (41.2°F).
- Average low temperature in January: 23.2°F
The month with the highest average low temperature is July (61.7°F).
The coldest month (with the lowest average low temperature) is December (21.9°F).
Average pressure in January
Thornton, CO
- Average pressure in January: 30.14"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are April and June (29.91"Hg).
Average wind speed in January
Thornton, CO
- Average wind speed in January: 6.1mph
The windiest month (with the highest average wind speed) is April (6.9mph).
The calmest month (with the lowest average wind speed) is December (5.8mph).
Average humidity in January
Thornton, CO
- Average humidity in January: 62%
The month with the highest relative humidity is February (64%).
The month with the lowest relative humidity is August (39%).
Average rainfall in January
Thornton, CO
- Average rainfall in January: 0.08"
The wettest month (with the highest rainfall) is July (0.59").
The driest months (with the least rainfall) are January and December (0.08").
Average rainfall days in January
Thornton, CO
- Average rainfall days in January: 2.3 days
The month with the highest number of rainy days is July (8.2 days).
The month with the least rainy days is February (1.2 days).
Average snowfall in January
Thornton, CO
- Average snowfall in January: 0.71"
The month with the highest snowfall is October (1.42").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in January
Thornton, CO
- Average snowfall days in January: 3.2 days
The month with the highest number of snowfall days is February (4.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in January /
Average sunshine in January
Thornton, CO
- Average daylight in January: 9h and 42min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in January: 7h and 0min
The months with the most sunshine are June and July (Average sunshine: 11h and 54min).
The month with the least sunshine is February (Average sunshine: 6h and 42min).
Average sunshine days in January
Thornton, CO
- Average sunshine days in January: 27.4 days
The month with the most sunshine days is December (28.5 days).
The month with the least sunshine days is July (19.6 days).
Average UV index in January
Thornton, CO
- 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
Thornton, CO
- Average cloud cover in January: 21
The months with the most cloud cover are February, April and May (Cloud cover 25).
The month with the least cloud cover is September (Cloud cover 14).
Average visibility in January
Thornton, CO
- 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).





