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
The onset of December results in a decrease in the average high-temperature, receding from a cold 36.5°F (2.5°C) in November to a freezing cold 23.9°F (-4.5°C). Grand Isle's nighttime temperature in December drops to an average of 12.2°F (-11°C).Humidity
In Grand Isle, the average relative humidity in December is 90%.Rainfall
In Grand Isle, in December, during 7.8 rainfall days, 2.76" (70mm) of precipitation is typically accumulated. In Grand Isle, during the entire year, the rain falls for 140.8 days and collects up to 30.12" (765mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Grand Isle, in December, during 17.8 snowfall days, 12.28" (312mm) of snow is typically accumulated. Throughout the year, there are 107.8 snowfall days, and 71.34" (1812mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 8h and 30min of daylight.On the first day of the month, sunrise is at 6:59 am and sunset at 3:44 pm. On the last day of December, sunrise is at 7:19 am and sunset at 3:52 pm EST.
Sunshine
In Grand Isle, the average sunshine in December is 2.9h.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a minimal health vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In December, a regular UV index of 1 translates into these guidelines:
Extended time in the sun generally does not harm most, but those with sensitive skin, infants, and children should always be protected. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Take heed! Reflection from the snow can almost amplify the Sun's UV radiation by double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
How many days does it rain in December?
How much does it snow in Grand Isle in December?
What is the month with the shortest days?
How many hours of daylight does Grand Isle have in December?
When is the sunrise / sunset in December?
How many hours of sunshine does Grand Isle have in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
Grand Isle, ME
- Average high temperature in December: 23.9°F
The warmest month (with the highest average high temperature) is July (74.3°F).
The month with the lowest average high temperature is January (18°F).
- Average low temperature in December: 12.2°F
The month with the highest average low temperature is July (53.6°F).
The coldest month (with the lowest average low temperature) is January (2.8°F).
Average pressure in December
Grand Isle, ME
- Average pressure in December: 30"Hg
The months with the highest atmospheric pressure are March, September and November (30.01"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in December
Grand Isle, ME
- Average wind speed in December: 7.7mph
The windiest months (with the highest average wind speed) are January and February (8.2mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in December
Grand Isle, ME
- Average humidity in December: 90%
The month with the highest relative humidity is March (94%).
The month with the lowest relative humidity is May (76%).
Average rainfall in December
Grand Isle, ME
- Average rainfall in December: 2.76"
The wettest month (with the highest rainfall) is April (2.95").
The driest month (with the least rainfall) is February (1.97").
Average rainfall days in December
Grand Isle, ME
- Average rainfall days in December: 7.8 days
The month with the highest number of rainy days is July (17.1 days).
The months with the least rainy days are January and February (4.3 days).
Average snowfall in December
Grand Isle, ME
- Average snowfall in December: 12.28"
The month with the highest snowfall is January (14.92").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Grand Isle, ME
- Average snowfall days in December: 17.8 days
The month with the highest number of snowfall days is January (21.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grand Isle, ME
- 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: 2h and 5min
The month with the most sunshine is August (Average sunshine: 9h and 30min).
The month with the least sunshine is February (Average sunshine: 2h and 6min).
Average sunshine days in December
Grand Isle, ME
- Average sunshine days in December: 11.5 days
The month with the most sunshine days is September (14.5 days).
The month with the least sunshine days is April (7.9 days).
Average UV index in December
Grand Isle, ME
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 1).
Average cloud cover in December
Grand Isle, ME
- Average cloud cover in December: 70
The month with the most cloud cover is February (Cloud cover 75).
The month with the least cloud cover is July (Cloud cover 42).
Average visibility in December
Grand Isle, ME
- Average visibility in December: 4mi
The months with the highest visibility are May, June, July, August, September, October and November (5mi).
The months with the lowest visibility are January, February, March, April and December (4mi).
Grand Isle, Maine, USA
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