Contents
- Weather in January
- Frequently asked questions
- Average temperature in January
- Average pressure in January
- Average wind speed in January
- Average humidity in January
- Average rainfall in January
- Average rainfall days in January
- Average snowfall in January
- Average snowfall days in January
- Average daylight in January
- Average sunshine in January
- Average sunshine days in January
- Average UV index in January
- Average cloud cover in January
- Average visibility in January
Weather in January
Temperature
January brings the lowest temperatures, with an average high of 33.8°F (1°C) and an average low of 21.6°F (-5.8°C).Humidity
In January, the average relative humidity is 78%.Rainfall
In Mount Gretna, in January, during 6.7 rainfall days, 1.06" (27mm) of precipitation is typically accumulated. In Mount Gretna, during the entire year, the rain falls for 137.4 days and collects up to 16.26" (413mm) of precipitation.Snowfall
Months with snowfall in Mount Gretna are January through May, October through December. January is the month with the most snowfall. Snow falls for 5.2 days and accumulates 1.97" (50mm) of snow.Daylight
The average length of the day in January is 9h and 41min.On the first day of the month, sunrise is at 7:28 am and sunset at 4:50 pm. On the last day of January, sunrise is at 7:15 am and sunset at 5:22 pm EST.
Sunshine
In January, the average sunshine in Mount Gretna is 4.6h.UV index
The months with the lowest UV index 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 unprotected exposure to Sun's UV rays for the ordinary person.Note: The UV index of 2 during January translates into the following guidance:
Most individuals face no significant issues with extended sun exposure, but it is always essential to protect children, babies, and those with sensitive skin. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly. Alert! The snow's reflection can amplify the UV radiation of the Sun nearly twice.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the coldest time of year?
How cold is it in January?
What is the average humidity in January?
How much does it rain in January?
What is the snowiest month?
How much does it snow in January?
How many hours of daylight does Mount Gretna have in January?
When are sunrise and sunset in January?
How many hours of sunshine does Mount Gretna have in January?
What is the month with the lowest UV index?
What is the UV index intensity in January?
Average temperature in January
Mount Gretna, PA
- Average high temperature in January: 33.8°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (33.8°F).
- Average low temperature in January: 21.6°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure in January
Mount Gretna, PA
- Average pressure in January: 30.09"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in January
Mount Gretna, PA
- Average wind speed in January: 8.5mph
The windiest month (with the highest average wind speed) is March (8.8mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in January
Mount Gretna, PA
- Average humidity in January: 78%
The months with the highest relative humidity are February, May and October (81%).
The month with the lowest relative humidity is April (76%).
Average rainfall in January
Mount Gretna, PA
- Average rainfall in January: 1.06"
The wettest month (with the highest rainfall) is August (2.13").
The driest month (with the least rainfall) is February (0.94").
Average rainfall days in January
Mount Gretna, PA
- Average rainfall days in January: 6.7 days
The month with the highest number of rainy days is May (15.9 days).
The month with the least rainy days is January (6.7 days).
Average snowfall in January
Mount Gretna, PA
- Average snowfall in January: 1.97"
The month with the highest snowfall is January (1.97").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in January
Mount Gretna, PA
- Average snowfall days in January: 5.2 days
The month with the highest number of snowfall days is January (5.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in January /
Average sunshine in January
Mount Gretna, PA
- Average daylight in January: 9h and 4min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in January: 4h and 4min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in January
Mount Gretna, PA
- Average sunshine days in January: 20.3 days
The month with the most sunshine days is January (20.3 days).
The month with the least sunshine days is May (11.5 days).
Average UV index in January
Mount Gretna, PA
- Average UV index in January: 2
The months with the highest UV index are May, June and July (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
Mount Gretna, PA
- Average cloud cover in January: 49
The months with the most cloud cover are February and December (Cloud cover 51).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in January
Mount Gretna, PA
- Average visibility in January: 6mi
The months with the highest visibility are January, February, March, April, June, July, November and December (6mi).
The months with the lowest visibility are May, August, September and October (5mi).
Mount Gretna, Pennsylvania, USA
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