Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December, recording an average high temperature of 31.6°F (-0.2°C) and a low temperature of 21.4°F (-5.9°C), is Hartline's coldest month.Humidity
The average relative humidity in December is 86%.Rainfall
The months with the most rainfall are May and December, with an average 1.18" (30mm) of precipitation.Snowfall
January through April, September through December are months with snowfall. In Hartline, during December, snow falls for 10.5 days and regularly aggregates up to 3.78" (96mm) of snow. Throughout the year, there are 33.4 snowfall days, and 14.65" (372mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 8h and 30min of daylight.On the first day of December, sunrise is at 7:24 am and sunset at 4:06 pm. On the last day of the month, sunrise is at 7:44 am and sunset at 4:14 pm PST.
Sunshine
The average sunshine in December is 4.4h.UV index
In Hartline, the average daily maximum UV index in December is 2. A UV Index of 2, and less, symbolizes a minimal health hazard from unsafe exposure to UV radiation for average individuals.Note: A daily maximum UV index of 2 in December translates into the following instructions:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. The Sun's radiation is especially intense around midday; try to stay in shade during this period. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Attention! Nearly twice the Sun's UV radiation can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What part of the year is the coldest?
How cold is December?
What is the average humidity in December?
What is the rainiest month?
How much does it rain in December?
How much does it snow in December?
What is the month with the shortest days in Hartline?
How many hours of daylight does Hartline have in December?
What time are sunrise and sunset in December?
How many hours of sunshine does Hartline have in December?
What is the UV index reading in December?
Average temperature in December
Hartline, WA
- Average high temperature in December: 31.6°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 December: 21.4°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 December
Hartline, WA
- Average pressure in December: 30.15"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 December
Hartline, WA
- Average wind speed in December: 5mph
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 December
Hartline, WA
- Average humidity in December: 86%
The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is August (36%).
Average rainfall in December
Hartline, WA
- Average rainfall in December: 1.18"
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 December
Hartline, WA
- Average rainfall days in December: 8.5 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 December
Hartline, WA
- Average snowfall in December: 3.78"
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 December
Hartline, WA
- Average snowfall days in December: 10.5 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 December /
Average sunshine in December
Hartline, WA
- Average daylight in December: 8h and 3min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in December: 4h and 2min
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 December
Hartline, WA
- Average sunshine days in December: 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 December
Hartline, WA
- Average UV index in December: 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 December
Hartline, WA
- Average cloud cover in December: 52
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 December
Hartline, WA
- Average visibility in December: 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).
Hartline, Washington, USA
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