January weather forecastUnderwood Heights, WA
January
Weather in January
January, like December, in Underwood Heights, Washington, is a wintry winter month, with an average temperature varying between 37°F (2.8°C) and 27.7°F (-2.4°C).Temperature
The transition from December to January sees an average high-temperature of a still icy 37°F (2.8°C), indicating a minor variance from the prior month. Throughout January, an average nighttime temperature of 27.7°F (-2.4°C) is experienced.Humidity
The average relative humidity in January in Underwood Heights, Washington, is 87%.Rainfall
January is the month with the most rainfall. Rain falls for 17.7 days and accumulates 5.67" (144mm) of precipitation.Snowfall
January through March, November and December are months with snowfall in Underwood Heights. In January, it is snowing for 3.4 days. Throughout January, 3.82" (97mm) of snow is accumulated. Throughout the year, there are 15.1 snowfall days, and 14.33" (364mm) of snow is accumulated.Daylight
In January, the average length of the day in Underwood Heights is 9h and 10min.On the first day of the month, sunrise is at 7:46 am and sunset at 4:32 pm. On the last day of January, sunrise is at 7:28 am and sunset at 5:10 pm PST.
Sunshine
January has the least sunshine of the year, with an average of 3.7h of sunshine.UV index
The months with the lowest UV index are January, February and November, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: The daily high UV index of 1 in January translates into this advice:
Extended exposure to the sun should always be avoided by children, infants, and those with sensitive skin. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear. Alert! The snow's reflection can amplify the UV radiation of the Sun nearly twice.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Underwood Heights, WA
- Average high temperature in January: 37°F
The warmest month (with the highest average high temperature) is August (78.4°F).
The month with the lowest average high temperature is December (36°F).
- Average low temperature in January: 27.7°F
The month with the highest average low temperature is August (51.4°F).
The coldest month (with the lowest average low temperature) is December (27°F).
Average pressure in January
Underwood Heights, WA
- Average pressure in January: 30.15"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is August (29.97"Hg).
Average wind speed in January
Underwood Heights, WA
- Average wind speed in January: 5.3mph
The windiest month (with the highest average wind speed) is June (6.1mph).
The calmest month (with the lowest average wind speed) is October (4.8mph).
Average humidity in January
Underwood Heights, WA
- Average humidity in January: 87%
The months with the highest relative humidity are February and December (88%).
The month with the lowest relative humidity is July (59%).
Average rainfall in January
Underwood Heights, WA
- Average rainfall in January: 5.67"
The wettest month (with the highest rainfall) is January (5.67").
The driest month (with the least rainfall) is July (0.28").
Average rainfall days in January
Underwood Heights, WA
- Average rainfall days in January: 17.7 days
The month with the highest number of rainy days is March (20 days).
The month with the least rainy days is August (4.2 days).
Average snowfall in January
Underwood Heights, WA
- Average snowfall in January: 3.82"
The month with the highest snowfall is February (4.76").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in January
Underwood Heights, WA
- Average snowfall days in January: 3.4 days
The month with the highest number of snowfall days is December (4.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in January /
Average sunshine in January
Underwood Heights, WA
- Average daylight in January: 9h and 12min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in January: 3h and 42min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in January
Underwood Heights, WA
- Average sunshine days in January: 10.2 days
The month with the most sunshine days is July (25.4 days).
The month with the least sunshine days is March (8.4 days).
Average UV index in January
Underwood Heights, WA
- Average UV index in January: 1
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February and November (UV index 1).
Average cloud cover in January
Underwood Heights, WA
- Average cloud cover in January: 64
The months with the most cloud cover are January and February (Cloud cover 64).
The months with the least cloud cover are July and August (Cloud cover 17).
Average visibility in January
Underwood Heights, WA
- Average visibility in January: 4mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February and December (4mi).





