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 sea temperature 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
With the beginning of May, Boston's average high-temperature sees an increase, transitioning from a fresh 55.2°F (12.9°C) in April to an enjoyable 66.4°F (19.1°C). May witnesses an average nighttime temperature of 50°F (10°C).Humidity
In Boston, the average relative humidity in May is 72%.Rainfall
In Boston, during May, the rain falls for 15.3 days and regularly aggregates up to 1.81" (46mm) of precipitation. In Boston, during the entire year, the rain falls for 141.4 days and collects up to 27.2" (691mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. May is the last month it regularly snows. During 0.1 snowfall days, in May, Boston aggregates 0.04" (1mm) of snow. In Boston, during the entire year, snow falls for 29.8 days and aggregates up to 15.75" (400mm) of snow.Ocean temperature
In Boston, the average seawater temperature in May is 49.1°F (9.5°C).Note: Diving into 49.1°F (9.5°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 May, the average length of the day is 14h and 37min.On the first day of May, sunrise is at 5:38 am and sunset at 7:44 pm. On the last day of the month, sunrise is at 5:10 am and sunset at 8:14 pm EDT.
Sunshine
The average sunshine in May is 8.3h.UV index
In Boston, the average daily maximum UV index in May is 5. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for the ordinary person.Note: A maximum high UV index of 5 in May translates into the following recommendations:
Stay alert. Light-skinned people could suffer burns in less than 30 minutes. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear. Be informed! The Sun's UV radiation can be nearly doubled due to the reflection from snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in May?
What is the average humidity in May?
How much does it rain in May?
What is the last month it snows?
What is the water temperature in May?
What is the average length of the day in May?
What time are sunrise and sunset in May?
How many hours of sunshine does Boston have in May?
What is the UV index reading in May?
Average temperature in May
Boston, MA
- Average high temperature in May: 66.4°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (34.2°F).
- Average low temperature in May: 50°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (22.6°F).
Average pressure in May
Boston, MA
- Average pressure in May: 30.01"Hg
The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in May
Boston, MA
- Average wind speed in May: 7.4mph
The windiest month (with the highest average wind speed) is January (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in May
Boston, MA
- Average humidity in May: 72%
The month with the highest relative humidity is February (77%).
The month with the lowest relative humidity is April (69%).
Average rainfall in May
Boston, MA
- Average rainfall in May: 1.81"
The wettest months (with the highest rainfall) are March, April and December (2.91").
The driest month (with the least rainfall) is September (1.26").
Average rainfall days in May
Boston, MA
- Average rainfall days in May: 15.3 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is January (7.9 days).
Average snowfall in May
Boston, MA
- Average snowfall in May: 0.04"
The month with the highest snowfall is February (4.72").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Boston, MA
- Average snowfall days in May: 0.1 days
The months with the highest number of snowfall days are January and February (7.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average sea temperature in May
Boston, MA
- Average sea temperature in May: 49.2°F
The best month for swimming (with the highest average sea temperature) is August (67.9°F).
The coldest month (with the lowest average sea temperature) is February (38.1°F).
Average daylight in May /
Average sunshine in May
Boston, MA
- Average daylight in May: 14h and 4min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in May: 8h and 2min
The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in May
Boston, MA
- Average sunshine days in May: 14.2 days
The month with the most sunshine days is September (17.7 days).
The month with the least sunshine days is April (13 days).
Average UV index in May
Boston, MA
- Average UV index in May: 5
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 May
Boston, MA
- Average cloud cover in May: 46
The month with the most cloud cover is March (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in May
Boston, MA
- Average visibility in May: 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).
Boston, Massachusetts, USA
Weather forecast for your location
2. Allow the app to use your location