December weather forecastIstro, Greece

December

Weather in December

The first month of the winter, December, is still a mild month in Istro, Greece, with an average temperature fluctuating between 15.9°C (60.6°F) and 13.3°C (55.9°F).

Temperature

Istro's transition into December involves a gentle shift in temperature, receding from a comfortable 19.3°C (66.7°F) in November to a still refreshing 15.9°C (60.6°F). The nighttime temperature in December experiences a minor dip, averaging a still moderate 13.3°C (55.9°F).

Humidity

January, February and December, with an average relative humidity of 72%, are the most humid months.

Rainfall

In Istro, in December, it is raining for 10.4 days, with typically 24mm (0.94") of accumulated precipitation. In Istro, during the entire year, the rain falls for 64.8 days and collects up to 119mm (4.69") of precipitation.

Sea temperature

In Istro, the average seawater temperature in December is 18°C (64.4°F).
Note: The majority of individuals find it unpleasurable to swim in 18°C (64.4°F). It becomes progressively harder to manage one's breathing as the water temperature falls below 21°C (69.8°F).

Daylight

With an average of 9h and 48min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 07:07 and sunset at 17:05. On the last day of December, sunrise is at 07:25 and sunset at 17:15 EET.

Sunshine

The average sunshine in December is 6.5h.

UV index

January through March and December, with an average maximum UV index of 4, are months with the lowest UV index. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.
Note: A maximum high UV index of 4 in December translates into the following recommendations:
Guard yourself - An obligation to protect skin and eyes from harm exists. The Sun's radiation is especially intense around midday; try to stay in shade during this period. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly.

Frequently asked questions

In Istro, in December, the average high-temperature is 15.9°C (60.6°F), and the average low-temperature is 13.3°C (55.9°F). The average heat index (a.k.a. 'felt air temperature', 'real feel'), which represents the influence of relative humidity on air temperature, in August is evaluated at 30°C (86°F).

The months with the highest humidity are January, February and December, with an average relative humidity of 72%.

The average relative humidity in December is 72%.

In Istro, during December, the rain falls for 10.4 days and regularly aggregates up to 24mm (0.94") of precipitation.

In Istro, in December, the average water temperature is 18°C (64.4°F). For swimming, a surface water temperature of 18°C (64.4°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).

The month with the shortest days is December, with an average of 9h and 48min of daylight.

In Istro, Greece, the average day length in December is 9h and 50min.

In December, on the first day of the month, sunrise is at 07:07 and sunset at 17:05. On the last day of the month, sunrise is at 07:25 and sunset at 17:15 EET.

In December, the average sunshine duration is 6.5h.

January through March and December, with an average maximum UV index of 4, are months with the lowest UV index.

The average daily maximum UV index in December is 4. A UV Index estimate of 3 to 5 represents a moderate health threat from unsafe exposure to Sun's UV rays.
Average high temperature
Average low temperature
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average sea temperature
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Istro, Greece

  • Average high temperature in December: 15.9°C

The warmest month (with the highest average high temperature) is August (28.1°C).
The month with the lowest average high temperature is January (14.2°C).

  • Average low temperature in December: 13.3°C

The month with the highest average low temperature is August (23.7°C).
The coldest month (with the lowest average low temperature) is January (11.5°C).

Average pressure in December
Istro, Greece

  • Average pressure in December: 1017.9mbar

The month with the highest atmospheric pressure is December (1017.9mbar).
The month with the lowest atmospheric pressure is July (1009mbar).

Average wind speed in December
Istro, Greece

  • Average wind speed in December: 18.8km/h

The windiest month (with the highest average wind speed) is January (20.6km/h).
The calmest month (with the lowest average wind speed) is May (12.6km/h).

Average humidity in December
Istro, Greece

  • Average humidity in December: 72%

The months with the highest relative humidity are January, February and December (72%).
The month with the lowest relative humidity is July (65%).

Average rainfall in December
Istro, Greece

  • Average rainfall in December: 24mm

The wettest month (with the highest rainfall) is January (25mm).
The driest month (with the least rainfall) is August (0mm).

Average rainfall days in December
Istro, Greece

  • Average rainfall days in December: 10.4 days

The month with the highest number of rainy days is December (10.4 days).
The month with the least rainy days is August (0.4 days).

Average sea temperature in December
Istro, Greece

  • Average sea temperature in December: 18°C

The best month for swimming (with the highest average sea temperature) is August (25°C).
The coldest months (with the lowest average sea temperature) are February and March (15°C).

Average daylight in December /
Average sunshine in December
Istro, Greece

  • Average daylight in December: 9h and 48min

The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).

  • Average sunshine in December: 6h and 30min

The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 6h and 24min).

Average sunshine days in December
Istro, Greece

  • Average sunshine days in December: 16.5 days

The months with the most sunshine days are July and August (30.3 days).
The month with the least sunshine days is January (15.9 days).

Average UV index in December
Istro, Greece

  • Average UV index in December: 4

The months with the highest UV index are July and August (UV index 7).
The months with the lowest UV index are January, February, March and December (UV index 4).

Average cloud cover in December
Istro, Greece

  • Average cloud cover in December: 29

The month with the most cloud cover is January (Cloud cover 31).
The months with the least cloud cover are July and August (Cloud cover 2).

Average visibility in December
Istro, Greece

  • Average visibility in December: 10km

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).