Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
Mount Gretna experiences a temperature shift with the start of May, with average high-temperatures moving from a mild 59.4°F (15.2°C) in April to an agreeable 68.7°F (20.4°C). An average low-temperature of 51.1°F (10.6°C) is noted during the month of May.Humidity
February, May and October, with an average relative humidity of 81%, are the most humid months.Rainfall
In Mount Gretna, during May, the rain falls for 15.9 days and regularly aggregates up to 1.61" (41mm) of precipitation. In Mount Gretna, during the entire year, the rain falls for 137.4 days and collects up to 16.26" (413mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. May is the last month it regularly snows. During 0.2 snowfall days, in May, Mount Gretna aggregates 0.04" (1mm) of snow. Throughout the year, there are 19.5 snowfall days, and 6.69" (170mm) of snow is accumulated.Daylight
The average length of the day in May is 14h and 26min.On the first day of May, sunrise is at 6:04 am and sunset at 8:01 pm. On the last day of the month, sunrise is at 5:38 am and sunset at 8:29 pm EDT.
Sunshine
In Mount Gretna, the average sunshine in May is 8.2h.UV index
The months with the highest UV index are May through July, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for the average person.Note: The maximum UV index of 6 during May translates into these guidelines:
Inhibit overexposure. Warding off sun damage is of utmost importance. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Warning! The reflection from snow can nearly magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in May?
What is the most humid month?
What is the average humidity in May in Mount Gretna?
How much does it rain in May?
What is the last month it snows?
What is the average length of the day in May?
When is the sunrise / sunset in May?
How many hours of sunshine does Mount Gretna have in May?
What is the month with the highest UV index?
How high is the UV index in May?
Average temperature in May
Mount Gretna, PA
- Average high temperature in May: 68.7°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 May: 51.1°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 May
Mount Gretna, PA
- Average pressure in May: 30.01"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 May
Mount Gretna, PA
- Average wind speed in May: 6.6mph
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 May
Mount Gretna, PA
- Average humidity in May: 81%
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 May
Mount Gretna, PA
- Average rainfall in May: 1.61"
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 May
Mount Gretna, PA
- Average rainfall days in May: 15.9 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 May
Mount Gretna, PA
- Average snowfall in May: 0.04"
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 May
Mount Gretna, PA
- Average snowfall days in May: 0.2 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 May /
Average sunshine in May
Mount Gretna, PA
- Average daylight in May: 14h and 2min
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 May: 8h and 1min
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 May
Mount Gretna, PA
- Average sunshine days in May: 11.5 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 May
Mount Gretna, PA
- Average UV index in May: 6
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 May
Mount Gretna, PA
- Average cloud cover in May: 48
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 May
Mount Gretna, PA
- Average visibility in May: 5mi
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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