December weather forecastRochester, NH
December
Weather in December
Returning to winter, December is characterized by decreasing temperatures and increased snowfall in Rochester, New Hampshire, USA. The city encounters an average temperature high of 35.6°F (2°C) and an average low of 24.6°F (-4.1°C), while the snowfall rises noticeably to 6.69" (170mm) from November's 1.5" (38mm). While the daylight hours limit outdoor activities, the snow-laden landscape adds a picturesque charm to the city. December marks the beginning of another winter season, dressed from head to toe in white, promising a snowy Christmas and a frosty New Year.Temperature
During the transition into December, Rochester observes a decrease in the average high-temperature, falling from a frosty 46°F (7.8°C) in November to an icy 35.6°F (2°C). December generally records an average low-temperature of 24.6°F (-4.1°C).Humidity
In Rochester, the average relative humidity in December is 80%.Rainfall
The months with the most rainfall in Rochester are October and December, with an average 3.11" (79mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. December is the month with the most snowfall. Snow falls for 7.2 days and accumulates 6.69" (170mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 0min of daylight.On the first day of December, sunrise is at 6:57 am and sunset at 4:09 pm. On the last day of the month, sunrise is at 7:16 am and sunset at 4:18 pm EST.
Sunshine
In December, the average sunshine is 4.8h.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for the average person.Note: In December, the maximum UV index of 2 suggests these recommendations:
Many can withstand an hour in the sun without burning, yet children must always have protection against sunlight. Avoiding direct sun during mid-day hours can prevent harmful UV radiation exposure. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Attention! Nearly twice the Sun's UV radiation can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rochester, NH
- Average high temperature in December: 35.6°F
The warmest month (with the highest average high temperature) is July (78.3°F).
The month with the lowest average high temperature is January (29.7°F).
- Average low temperature in December: 24.6°F
The month with the highest average low temperature is July (60.3°F).
The coldest month (with the lowest average low temperature) is January (17.4°F).
Average pressure in December
Rochester, NH
- 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
Rochester, NH
- Average wind speed in December: 8.5mph
The windiest month (with the highest average wind speed) is January (9.3mph).
The calmest months (with the lowest average wind speed) are July and August (5.5mph).
Average humidity in December
Rochester, NH
- Average humidity in December: 80%
The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is April (75%).
Average rainfall in December
Rochester, NH
- Average rainfall in December: 3.11"
The wettest months (with the highest rainfall) are October and December (3.11").
The driest month (with the least rainfall) is September (1.5").
Average rainfall days in December
Rochester, NH
- Average rainfall days in December: 10 days
The month with the highest number of rainy days is May (15.1 days).
The month with the least rainy days is February (6.8 days).
Average snowfall in December
Rochester, NH
- Average snowfall in December: 6.69"
The month with the highest snowfall is December (6.69").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Rochester, NH
- Average snowfall days in December: 7.2 days
The month with the highest number of snowfall days is January (10.4 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Rochester, NH
- Average daylight in December: 9h and 0min
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 0min).
- Average sunshine in December: 4h and 48min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in December
Rochester, NH
- Average sunshine days in December: 16.1 days
The month with the most sunshine days is November (16.9 days).
The month with the least sunshine days is April (13.3 days).
Average UV index in December
Rochester, NH
- Average UV index in December: 2
The months with the highest UV index are 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
Rochester, NH
- 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 32).
Average visibility in December
Rochester, NH
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, October, November and December (6mi).
The months with the lowest visibility are May, June, July, August and September (5mi).





