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
With December's onset, the weather shows a temperature decrease, transitioning from a mild 14.9°C (58.8°F) in November to a frosty 8.9°C (48°F). Koyasan observes an average nighttime temperature of 2.5°C (36.5°F) during December.Humidity
In Koyasan, the average relative humidity in December is 78%.Rainfall
In December, in Koyasan, the rain falls for 16.7 days. Throughout December, 66mm (2.6") of precipitation is accumulated. In Koyasan, Japan, during the entire year, the rain falls for 199.5 days and collects up to 1277mm (50.28") of precipitation.Snowfall
January through April and December are months with snowfall in Koyasan, Japan. December is the first month it typically snows. Throughout December, in the average 4.9 snowfall days, it receives 35mm (1.38") of snow. Throughout the year, in Koyasan, there are 25.9 snowfall days, and 201mm (7.91") of snow is accumulated.Daylight
December has the shortest days of the year in Koyasan, with an average of 9h and 54min of daylight.On the first day of December, sunrise is at 06:45 and sunset at 16:48. On the last day of the month, sunrise is at 07:03 and sunset at 16:58 JST.
Sunshine
In December, the average sunshine is 5.3h.UV index
The months with the lowest UV index in Koyasan are January, February and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a minimal health hazard from exposure to the Sun's UV rays for the average person.Note: During December, 2 as the daily maximum UV index converts into the following advice:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. It's recommended to limit sun exposure when its radiation is at its peak during midday. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Be alert! Nearly double the UV rays from the Sun can be reflected by snow.
Frequently asked questions
What are December temperatures in Koyasan?
What is the average humidity in December in Koyasan?
How many days does it rain in December in Koyasan?
When does it start to snow in Koyasan?
What is the month with the shortest days in Koyasan?
How many hours of daylight does Koyasan have in December?
When are sunrise and sunset in December in Koyasan?
How long on average sun shines in December in Koyasan?
When is the lowest UV index in Koyasan?
How high is the UV index in December in Koyasan?
Average temperature in December
Koyasan, Japan
- Average high temperature in December: 8.9°C
The warmest month (with the highest average high temperature) is August (29.9°C).
The month with the lowest average high temperature is January (6.7°C).
- Average low temperature in December: 2.5°C
The month with the highest average low temperature is August (22.3°C).
The coldest month (with the lowest average low temperature) is January (0.1°C).
Average pressure in December
Koyasan, Japan
- Average pressure in December: 1019.2mbar
The month with the highest atmospheric pressure is February (1019.5mbar).
The month with the lowest atmospheric pressure is June (1008.8mbar).
Average wind speed in December
Koyasan, Japan
- Average wind speed in December: 9km/h
The windiest month (with the highest average wind speed) is January (9.5km/h).
The calmest months (with the lowest average wind speed) are June and August (6.2km/h).
Average humidity in December
Koyasan, Japan
- Average humidity in December: 78%
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is May (74%).
Average rainfall in December
Koyasan, Japan
- Average rainfall in December: 66mm
The wettest month (with the highest rainfall) is July (179mm).
The driest month (with the least rainfall) is January (56mm).
Average rainfall days in December
Koyasan, Japan
- Average rainfall days in December: 16.7 days
The month with the highest number of rainy days is July (21.1 days).
The month with the least rainy days is February (13.8 days).
Average snowfall in December
Koyasan, Japan
- Average snowfall in December: 35mm
The month with the highest snowfall is January (90mm).
The months with the least snowfall are May, June, July, August, September, October and November (0mm).
Average snowfall days in December
Koyasan, Japan
- Average snowfall days in December: 4.9 days
The month with the highest number of snowfall days is January (11.1 days).
The months with the least snowfall days are May, June, July, August, September, October and November (0 days).
Average daylight in December /
Average sunshine in December
Koyasan, Japan
- Average daylight in December: 9h and 5min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in December: 5h and 2min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The months with the least sunshine are January and February (Average sunshine: 5h and 12min).
Average sunshine days in December
Koyasan, Japan
- Average sunshine days in December: 8.8 days
The month with the most sunshine days is May (14.3 days).
The month with the least sunshine days is July (7.9 days).
Average UV index in December
Koyasan, Japan
- Average UV index in December: 2
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in December
Koyasan, Japan
- Average cloud cover in December: 43
The month with the most cloud cover is January (Cloud cover 46).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in December
Koyasan, Japan
- Average visibility in December: 9km
The months with the highest visibility are January, February, March, April, May, August, September, October, November and December (9km).
The months with the lowest visibility are June and July (8km).
Koyasan, Japan
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