January weather forecastGrand Coulee, WA
January
Weather in January
January is a wintry winter month in Grand Coulee, Washington, with an average temperature fluctuating between 32°F (0°C) and 21.9°F (-5.6°C).Temperature
Grand Coulee's transition from December to January introduces an average high-temperature of an icy 32°F (0°C), marking an insignificant variation from the 31.6°F (-0.2°C). The average temperature drops to a subzero cold 21.9°F (-5.6°C) during the night in the month of January.Humidity
With an average relative humidity of 89%, January is the most humid month.Rainfall
In January, the rain falls for 9.7 days. Throughout January, 1.14" (29mm) of precipitation is accumulated. In Grand Coulee, during the entire year, the rain falls for 102.1 days and collects up to 9.65" (245mm) of precipitation.Snowfall
Months with snowfall are January through April, September through December. The month with the most snowfall is January, when snow falls for 8.4 days and typically aggregates up to 4.41" (112mm) of snow.Daylight
The average length of the day in January is 8h and 55min.On the first day of January, sunrise is at 7:45 am and sunset at 4:13 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 4:54 pm PST.
Sunshine
January has the least sunshine of the year, with an average of 4.1h of sunshine.UV index
In Grand Coulee, the average daily maximum UV index in January is 2. A UV Index value of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV radiation for the average person.Note: The UV index of 2 during January leads to these advisories:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. To protect against the Sun's most potent rays, avoid direct exposure around midday. During bright days, sunglasses that offer UVA and UVB defense are recommended. Take to heart! Snow reflection can almost magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Grand Coulee, WA
- Average high temperature in January: 32°F
The warmest month (with the highest average high temperature) is July (84.9°F).
The month with the lowest average high temperature is December (31.6°F).
- Average low temperature in January: 21.9°F
The month with the highest average low temperature is August (61.3°F).
The coldest month (with the lowest average low temperature) is December (21.4°F).
Average pressure in January
Grand Coulee, WA
- Average pressure in January: 30.18"Hg
The month with the highest atmospheric pressure is January (30.18"Hg).
The month with the lowest atmospheric pressure is August (29.91"Hg).
Average wind speed in January
Grand Coulee, WA
- Average wind speed in January: 4.9mph
The windiest month (with the highest average wind speed) is April (7mph).
The calmest month (with the lowest average wind speed) is January (4.9mph).
Average humidity in January
Grand Coulee, WA
- Average humidity in January: 89%
The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is August (36%).
Average rainfall in January
Grand Coulee, WA
- Average rainfall in January: 1.14"
The wettest months (with the highest rainfall) are May and December (1.18").
The driest months (with the least rainfall) are July and August (0.2").
Average rainfall days in January
Grand Coulee, WA
- Average rainfall days in January: 9.7 days
The month with the highest number of rainy days is March (12.1 days).
The month with the least rainy days is August (3.2 days).
Average snowfall in January
Grand Coulee, WA
- Average snowfall in January: 4.41"
The month with the highest snowfall is January (4.41").
The months with the least snowfall are May, June, July and August (0").
Average snowfall days in January
Grand Coulee, WA
- Average snowfall days in January: 8.4 days
The month with the highest number of snowfall days is December (10.5 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in January /
Average sunshine in January
Grand Coulee, WA
- Average daylight in January: 8h and 54min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in January: 4h and 6min
The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in January
Grand Coulee, WA
- Average sunshine days in January: 16 days
The month with the most sunshine days is August (25.8 days).
The month with the least sunshine days is March (14.7 days).
Average UV index in January
Grand Coulee, WA
- Average UV index in January: 2
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is November (UV index 1).
Average cloud cover in January
Grand Coulee, WA
- 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 August (Cloud cover 12).
Average visibility in January
Grand Coulee, WA
- Average visibility in January: 4mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (4mi).





