January weather forecastGreenwich, CT
January
Weather in January
January bustles with the chill of winter in Greenwich, Connecticut, USA. The mountainscape appears stunning under the blanket of snow, adding to the city's winter charm. Notably, the lowest temperature records fall between 26.1°F (-3.3°C) to 35.8°F (2.1°C), indicating a frosty ambiance. The city's characteristic morning fog adds a mystical undertone to the crisp January air. With nearly 45% cloud cover, Greenwich provides a picturesque postcard setting for winter enthusiasts.Temperature
The coldest period in Greenwich tends to be January, when average temperatures fluctuate between a high of 35.8°F (2.1°C) and a low of 26.1°F (-3.3°C).Humidity
In Greenwich, the average relative humidity in January is 74%.Rainfall
The months with the least rainfall in Greenwich are January and February Rain falls for 7.9 days and accumulates 2.4" (61mm) of rain.Snowfall
Months with snowfall are January through April, November and December. In Greenwich, in January, during 7.2 snowfall days, 1.97" (50mm) of snow is typically accumulated. Throughout the year, in Greenwich, there are 25.5 snowfall days, and 8.78" (223mm) of snow is accumulated.Ocean temperature
In Greenwich, the average seawater temperature in January is 41.7°F (5.4°C).Note: Diving into 41.7°F (5.4°C) is practical below 50°F (10°C), given you're wearing protective swim gear; without it, expect a quick onset of cold shock and a struggle to breathe. Merely touching waters at 55.4°F (13°C) feels ice-cold.
Daylight
In Greenwich, the average length of the day in January is 9h and 37min.On the first day of the month, sunrise is at 7:19 am and sunset at 4:36 pm. On the last day of January, sunrise is at 7:06 am and sunset at 5:09 pm EST.
Sunshine
The average sunshine in January in Greenwich, Connecticut, is 5h.UV index
The months with the lowest UV index in Greenwich are January through March, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low health risk from exposure to the Sun's UV radiation for ordinary individuals.Note: The maximum UV index of 2 during January translates into these guidelines:
Although prolonged sun exposure does not typically bother most people, children, babies, and those with sensitive skin should always have protection. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears. Take careful note! The UV radiation of the Sun can be nearly doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Greenwich, CT
- Average high temperature in January: 35.8°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (35.8°F).
- Average low temperature in January: 26.1°F
The month with the highest average low temperature is July (69.1°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).
Average pressure in January
Greenwich, CT
- Average pressure in January: 30.05"Hg
The month with the highest atmospheric pressure is November (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in January
Greenwich, CT
- Average wind speed in January: 9.9mph
The windiest month (with the highest average wind speed) is January (9.9mph).
The calmest month (with the lowest average wind speed) is July (6.5mph).
Average humidity in January
Greenwich, CT
- Average humidity in January: 74%
The months with the highest relative humidity are February, May and December (75%).
The month with the lowest relative humidity is August (71%).
Average rainfall in January
Greenwich, CT
- Average rainfall in January: 2.4"
The wettest month (with the highest rainfall) is July (4.13").
The driest months (with the least rainfall) are January and February (2.4").
Average rainfall days in January
Greenwich, CT
- Average rainfall days in January: 7.9 days
The month with the highest number of rainy days is July (18.1 days).
The month with the least rainy days is January (7.9 days).
Average snowfall in January
Greenwich, CT
- Average snowfall in January: 1.97"
The month with the highest snowfall is February (2.52").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in January
Greenwich, CT
- Average snowfall days in January: 7.2 days
The month with the highest number of snowfall days is January (7.2 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average sea temperature in January
Greenwich, CT
- Average sea temperature in January: 41.6°F
The best month for swimming (with the highest average sea temperature) is August (73.1°F).
The coldest month (with the lowest average sea temperature) is February (39.5°F).
Average daylight in January /
Average sunshine in January
Greenwich, CT
- Average daylight in January: 9h and 36min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January: 5h and 0min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in January
Greenwich, CT
- Average sunshine days in January: 17.6 days
The month with the most sunshine days is November (17.8 days).
The month with the least sunshine days is June (10.7 days).
Average UV index in January
Greenwich, CT
- Average UV index in January: 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 January
Greenwich, CT
- Average cloud cover in January: 45
The month with the most cloud cover is December (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in January
Greenwich, CT
- Average visibility in January: 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).
