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 sea temperature 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
December
Weather in December
Temperature
December's average high-temperature in Greystones stands at a chilly 8.5°C (47.3°F), showing little deviation from November's 10.1°C (50.2°F). Greystones's nights throughout December are marked by an average low temperature of 5.4°C (41.7°F), a minor drop from the day's high.Humidity
In Greystones, the average relative humidity in December is 84%.Rainfall
In Greystones, in December, it is raining for 17 days, with typically 55mm (2.17") of accumulated precipitation. In Greystones, during the entire year, the rain falls for 200.5 days and collects up to 530mm (20.87") of precipitation.Snowfall
January through March, November and December are months with snowfall in Greystones. December is the month with the most snowfall. Snow falls for 1.1 days and accumulates 9mm (0.35") of snow.Sea temperature
In Greystones, the average seawater temperature in December is 11.3°C (52.3°F).Note: Navigating the 11.3°C (52.3°F) at 13°C (55.4°F) is no joy, and temperatures less than 10°C (50°F) can threaten breathing and cause a chilling shock, gauging personal stamina.
Daylight
December has the shortest days of the year, with an average of 7h and 36min of daylight.On the first day of the month, sunrise is at 8:16 am and sunset at 4:10 pm. On the last day of December, in Greystones, sunrise is at 8:38 am and sunset at 4:16 pm GMT.
Sunshine
The average sunshine in December in Greystones is 4.6h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Greystones. A UV Index estimate of 2, and below, represents a minimal health hazard from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The UV index of 2 during December leads to these advisories:
It is important to always shield children, babies, and individuals with sensitive skin from prolonged exposure to the sun. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Greystones in December?
What is the average humidity in December in Greystones?
How many days does it rain in December in Greystones?
What is the snowiest month in Greystones?
How much does it snow in Greystones in December?
What is the water temperature in December in Greystones?
What is the month with the shortest days in Greystones?
What is the average length of the day in December in Greystones?
When is the sunrise / sunset in December in Greystones?
How long on average sun shines in December in Greystones?
When is the lowest UV index in Greystones?
What is the UV index intensity in December in Greystones?
Average temperature in December
Greystones, Ireland
- Average high temperature in December: 8.5°C
The warmest months (with the highest average high temperature) are July and August (16.9°C).
The months with the lowest average high temperature are January and February (7.8°C).
- Average low temperature in December: 5.4°C
The month with the highest average low temperature is August (12.7°C).
The coldest month (with the lowest average low temperature) is February (4.4°C).
Average pressure in December
Greystones, Ireland
- Average pressure in December: 1011.1mbar
The month with the highest atmospheric pressure is May (1016mbar).
The month with the lowest atmospheric pressure is November (1008.3mbar).
Average wind speed in December
Greystones, Ireland
- Average wind speed in December: 25.9km/h
The windiest month (with the highest average wind speed) is December (25.9km/h).
The calmest month (with the lowest average wind speed) is July (15.9km/h).
Average humidity in December
Greystones, Ireland
- Average humidity in December: 84%
The month with the highest relative humidity is July (86%).
The month with the lowest relative humidity is March (82%).
Average rainfall in December
Greystones, Ireland
- Average rainfall in December: 55mm
The wettest month (with the highest rainfall) is November (71mm).
The driest month (with the least rainfall) is May (27mm).
Average rainfall days in December
Greystones, Ireland
- Average rainfall days in December: 17 days
The month with the highest number of rainy days is July (20.4 days).
The months with the least rainy days are March and September (14.9 days).
Average snowfall in December
Greystones, Ireland
- Average snowfall in December: 9mm
The month with the highest snowfall is December (9mm).
The months with the least snowfall are April, May, June, July, August, September and October (0mm).
Average snowfall days in December
Greystones, Ireland
- Average snowfall days in December: 1.1 days
The months with the highest number of snowfall days are January and February (1.3 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average sea temperature in December
Greystones, Ireland
- Average sea temperature in December: 11.3°C
The best month for swimming (with the highest average sea temperature) is August (14.9°C).
The coldest month (with the lowest average sea temperature) is March (8.4°C).
Average daylight in December /
Average sunshine in December
Greystones, Ireland
- Average daylight in December: 7h and 4min
The month with the longest days is June (Average daylight: 16h and 54min).
The month with the shortest days is December (Average daylight: 7h and 36min).
- Average sunshine in December: 4h and 4min
The month with the most sunshine is May (Average sunshine: 8h and 0min).
The month with the least sunshine is November (Average sunshine: 4h and 18min).
Average sunshine days in December
Greystones, Ireland
- Average sunshine days in December: 10.2 days
The month with the most sunshine days is April (11.7 days).
The month with the least sunshine days is July (7.2 days).
Average UV index in December
Greystones, Ireland
- Average UV index in December: 2
The months with the highest UV index are May, June, July, August and September (UV index 4).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Greystones, Ireland
- Average cloud cover in December: 53
The months with the most cloud cover are February and November (Cloud cover 56).
The month with the least cloud cover is September (Cloud cover 48).
Average visibility in December
Greystones, Ireland
- Average visibility in December: 9km
The months with the highest visibility are January, March, October and November (10km).
The months with the lowest visibility are February, April, May, June, July, August, September and December (9km).
