December weather forecastHiroshima, Japan

December

Weather in December

December in Hiroshima indicates the return of winter with temperatures dropping, snowfall reappearing at 30mm (1.18"), and daylight dwindling. The rainfall lessens, reaching the lowest point of the year, echoing typical winter patterns. Changes in sea temperatures, now decreasing, signal the final goodbye to any remaining warm summer conditions. The weather darkens earlier with the sunlight hours shortening to their smallest span for the year. The UV index hits its lowest, rounding off Hiroshima's climatic cycle for the year comfortably.

Temperature

The beginning of December involves a decrease in the average high-temperature, transitioning from a comfortable 17.4°C (63.3°F) in November to a cool 12.3°C (54.1°F). Hiroshima experiences an average low-temperature of 3.7°C (38.7°F) in month of December.

Humidity

The average relative humidity in December in Hiroshima is 69%.

Rainfall

The month with the least rainfall is December, when the rain falls for 17 days and typically collects 41mm (1.61") of precipitation.

Snowfall

January through March and December are months with snowfall. December is the first month it typically snows in Hiroshima. Throughout December, in the average 4.5 snowfall days, it receives 30mm (1.18") of snow. In Hiroshima, during the entire year, snow falls for 23.1 days and aggregates up to 130mm (5.12") of snow.

Sea temperature

In Hiroshima, the average seawater temperature in December is 16.8°C (62.2°F).
Note: A majority do not enjoy swimming in water at 16.8°C (62.2°F). The difficulty in controlling breathing increases progressively as the temperature dips below 21°C (69.8°F).

Daylight

December has the shortest days of the year in Hiroshima, with an average of 9h and 54min of daylight.
On the first day of the month, sunrise is at 06:58 and sunset at 17:00. On the last day of December, sunrise is at 07:16 and sunset at 17:10 JST.

Sunshine

In December, the average sunshine is 4.8h.

UV index

January and December, with an average maximum UV index of 3, are months with the lowest UV index. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for average individuals.
Note: In December, a daily UV index of 3 turns into the following recommendations:
Guard yourself - An obligation to protect skin and eyes from harm exists. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Mark this! Snow reflection can nearly double the UV radiation intensity from the Sun.

Updated: Jan 31, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

December temperatures in Hiroshima, Japan, vary between a high-temperature of 12.3°C (54.1°F) and a low-temperature of 3.7°C (38.7°F). In September, the average heat index (a.k.a. 'feels like', 'apparent temperature'), which factors the actual air temperature with the relative humidity, is appraised at 33°C (91.4°F).

The average relative humidity in December in Hiroshima, Japan, is 69%.

The month with the least rainfall in Hiroshima is December, when the rain falls for 17 days and typically collects 41mm (1.61") of precipitation.

In Hiroshima, in December, it is raining for 17 days, with typically 41mm (1.61") of accumulated precipitation.

December is the first month it typically snows. Throughout December, in the average 4.5 snowfall days, it receives 30mm (1.18") of snow.

In Hiroshima, Japan, in December, the average water temperature is 16.8°C (62.2°F). For swimming, a surface water temperature of 16.8°C (62.2°F) is not enjoyable for the majority. It is not considered safe, as controlling breathing becomes progressively more difficult as water temperature decreases below 21°C (69.8°F).

With an average of 9h and 54min of daylight, December has the shortest days of the year in Hiroshima, Japan.

The average day length in December is 9h and 54min.

In December, on the first day of the month, sunrise is at 06:58 and sunset at 17:00. On the last day of the month, in Hiroshima, sunrise is at 07:16 and sunset at 17:10 JST.

In Hiroshima, the average sunshine duration in December is 4.8h.

January and December, with an average maximum UV index of 3, are months with the lowest UV index.

In Hiroshima, Japan, the average daily maximum UV index in December is 3. A UV Index value of 3 to 5 symbolizes a medium health risk from unsafe exposure to Sun's UV rays.

Today

Tomorrow

Long-term

Year J F M A M J J A S O N December

Nov

December

Jan

Average high temperature

17.4°C

12.3°C

9.7°C

Average low temperature

Average humidity

Average rainfall

Average rainfall days

Average snowfall

0mm

30mm

50mm

Average snowfall days

0.2

4.5

8.7

Average sea temperature

Average daylight

Average sunshine

Average UV index

Average temperature in December
Hiroshima, Japan

Average high temperature in December: 12.3°C

The warmest month (with the highest average high temperature) is August (32.5°C).
The month with the lowest average high temperature is January (9.7°C).

Average low temperature in December: 3.7°C

The month with the highest average low temperature is August (24.8°C).
The coldest month (with the lowest average low temperature) is January (1.7°C).

Average humidity in December
Hiroshima, Japan

Average humidity in December: 69%

The month with the highest relative humidity is July (74%).
The month with the lowest relative humidity is April (63%).

Average rainfall in December
Hiroshima, Japan

Average rainfall in December: 41.2mm

The wettest month (with the highest rainfall) is July (258.6mm).
The driest month (with the least rainfall) is December (41.2mm).

Average rainfall days in December
Hiroshima, Japan

Average rainfall days in December: 17 days

The month with the highest number of rainy days is January (19 days).
The month with the least rainy days is October (12 days).

Average snowfall in December
Hiroshima, Japan

Average snowfall in December: 30mm

The month with the highest snowfall is January (50mm).
The months with the least snowfall are April, May, June, July, August, September, October and November (0mm).

Average snowfall days in December
Hiroshima, Japan

Average snowfall days in December: 4.5 days

The month with the highest number of snowfall days is January (8.7 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).

Average sea temperature in December
Hiroshima, Japan

Average sea temperature in December: 16.8°C

The best month for swimming (with the highest average sea temperature) is August (26.8°C).
The coldest month (with the lowest average sea temperature) is February (12.4°C).

Average daylight in December /
Average sunshine in December
Hiroshima, Japan

Average daylight in December: 9h and 54min

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: 4h and 48min

The month with the most sunshine is August (Average sunshine: 6h and 48min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).