August weather forecastChelsea, MA
August
Weather in August
August, the last month of the summer in Chelsea, is also a moderately hot month, with an average temperature varying between 64°F (17.8°C) and 80.4°F (26.9°C).Temperature
The commencement of August records an average high-temperature of a still moderately hot 80.4°F (26.9°C), barely varying from July's 81.7°F (27.6°C). An average temperature of 64°F (17.8°C) marks the nights in August.Humidity
In Chelsea, the average relative humidity in August is 72%.Rainfall
In Chelsea, in August, during 11.7 rainfall days, 1.61" (41mm) of precipitation is typically accumulated. Throughout the year, there are 141.4 rainfall days, and 27.2" (691mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Ocean temperature
August is the month with the warmest seawater, with an average ocean temperature of 68°F (20°C).Note: For the majority, swimming in 68°F (20°C) does not offer a pleasant experience. Below 69.8°F (21°C), the difficulty in controlling breathing escalates.
Daylight
In Chelsea, the average length of the day in August is 13h and 51min.On the first day of the month, sunrise is at 5:37 am and sunset at 8:03 pm. On the last day of August, sunrise is at 6:09 am and sunset at 7:19 pm EDT.
Sunshine
August has the most sunshine of the year in Chelsea, with an average of 10.5h of sunshine.UV index
June through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In August, the maximum UV index of 6 translates into these guidelines:
Incorporate safeguards and honour sun safety principles. Protection from skin and eye damage is obligatory. The time between 10 a.m. and 4 p.m. is when UV radiation is at its peak. Limit exposure to direct sunlight during these hours. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Chelsea, MA
- Average high temperature in August: 80.4°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 August: 64°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 August
Chelsea, MA
- Average pressure in August: 29.98"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 August
Chelsea, MA
- Average wind speed in August: 6.2mph
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 August
Chelsea, MA
- Average humidity in August: 72%
The month with the highest relative humidity is February (77%).
The month with the lowest relative humidity is April (69%).
Average rainfall in August
Chelsea, MA
- Average rainfall in August: 1.61"
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 August
Chelsea, MA
- Average rainfall days in August: 11.7 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 August
Chelsea, MA
- Average snowfall in August: 0"
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 August
Chelsea, MA
- Average snowfall days in August: 0 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 August
Chelsea, MA
- Average sea temperature in August: 67.9°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 August /
Average sunshine in August
Chelsea, MA
- Average daylight in August: 13h and 48min
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 August: 10h and 30min
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 August
Chelsea, MA
- Average sunshine days in August: 17 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 August
Chelsea, MA
- Average UV index in August: 6
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 August
Chelsea, MA
- Average cloud cover in August: 32
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 August
Chelsea, MA
- Average visibility in August: 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).





