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
During Merrimac's transition into December, the average high-temperature lessens, moving from a chilly 48.2°F (9°C) in November to a cold 37.9°F (3.3°C). Merrimac experiences a mean temperature of 27.7°F (-2.4°C) during December nights.Humidity
The average relative humidity in December is 77%.Rainfall
In December, in Merrimac, the rain falls for 4.8 days. Throughout December, 0.51" (13mm) of precipitation is accumulated. Throughout the year, there are 78.3 rainfall days, and 5.43" (138mm) of precipitation is accumulated.Snowfall
Months with snowfall in Merrimac are January through May, November and December. The month with the most snowfall in Merrimac is December, when snow falls for 2.6 days and typically aggregates up to 0.71" (18mm) of snow.Daylight
With an average of 9h and 6min of daylight, December has the shortest days of the year in Merrimac.On the first day of the month, sunrise is at 6:55 am and sunset at 4:10 pm. On the last day of December, sunrise is at 7:14 am and sunset at 4:19 pm EST.
Sunshine
In December, the average sunshine in Merrimac is 4.9h.UV index
The months with the lowest UV index in Merrimac are January through March, November and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for average individuals.Note: In December, a daily maximum UV index of 2 leads to the following instructions:
Most people face no serious problems with extended sun exposure, but those with fair skin, infants, and children always need protection. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. Mark this! Snow reflection can nearly double the UV radiation intensity from the Sun.
Frequently asked questions
How cold does it get in Merrimac in December?
What is the average humidity in December in Merrimac?
How much does it rain in Merrimac in December?
What is the snowiest month in Merrimac?
How much does it snow in Merrimac in December?
What is the month with the shortest days in Merrimac?
How many hours of daylight does Merrimac have in December?
What time are sunrise and sunset in December in Merrimac?
How long on average sun shines in December in Merrimac?
When is the lowest UV index in Merrimac?
What is the UV index reading in December in Merrimac?
Average temperature in December
Merrimac, MA
- Average high temperature in December: 37.9°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (32.5°F).
- Average low temperature in December: 27.7°F
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (20.5°F).
Average pressure in December
Merrimac, MA
- Average pressure in December: 30.03"Hg
The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Merrimac, MA
- Average wind speed in December: 8.9mph
The windiest month (with the highest average wind speed) is January (9.5mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).
Average humidity in December
Merrimac, MA
- Average humidity in December: 77%
The month with the highest relative humidity is February (79%).
The month with the lowest relative humidity is April (71%).
Average rainfall in December
Merrimac, MA
- Average rainfall in December: 0.51"
The wettest month (with the highest rainfall) is November (0.67").
The driest month (with the least rainfall) is September (0.2").
Average rainfall days in December
Merrimac, MA
- Average rainfall days in December: 4.8 days
The month with the highest number of rainy days is July (8.8 days).
The month with the least rainy days is January (3.6 days).
Average snowfall in December
Merrimac, MA
- Average snowfall in December: 0.71"
The month with the highest snowfall is December (0.71").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in December
Merrimac, MA
- Average snowfall days in December: 2.6 days
The month with the highest number of snowfall days is February (5.3 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Merrimac, MA
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in December: 4h and 5min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in December
Merrimac, MA
- Average sunshine days in December: 23 days
The month with the most sunshine days is January (24.5 days).
The month with the least sunshine days is April (18.4 days).
Average UV index in December
Merrimac, MA
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in December
Merrimac, MA
- Average cloud cover in December: 47
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in December
Merrimac, MA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Merrimac, Massachusetts, USA
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