September weather forecastHarvard, MA
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Harvard, Massachusetts, with temperature in the range of an average high of 73°F (22.8°C) and an average low of 54.5°F (12.5°C).Temperature
As September arrives, Harvard's weather displays a minor decrease in high-temperatures, transitioning from August's warm 80.6°F (27°C) to a pleasant 73°F (22.8°C). In September, the average low-temperature is a fresh 54.5°F (12.5°C).Humidity
In September, the average relative humidity is 77%.Rainfall
The month with the least rainfall is September, when the rain falls for 11.1 days and typically collects 1.38" (35mm) of precipitation.Snowfall
In Harvard, snow does not fall in June through September.Daylight
In Harvard, Massachusetts, the average length of the day in September is 12h and 29min.On the first day of September, sunrise is at 6:12 am and sunset at 7:20 pm. On the last day of the month, sunrise is at 6:43 am and sunset at 6:29 pm EDT.
Sunshine
In Harvard, the average sunshine in September is 8.2h.UV index
In Harvard, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Harvard, MA
- Average high temperature in September: 73°F
The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is January (32.5°F).
- Average low temperature in September: 54.5°F
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).
Average pressure in September
Harvard, MA
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.07"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Harvard, MA
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is January (8.5mph).
The calmest months (with the lowest average wind speed) are July and August (5.5mph).
Average humidity in September
Harvard, MA
- Average humidity in September: 77%
The month with the highest relative humidity is February (80%).
The month with the lowest relative humidity is April (70%).
Average rainfall in September
Harvard, MA
- Average rainfall in September: 1.38"
The wettest month (with the highest rainfall) is October (2.68").
The driest month (with the least rainfall) is September (1.38").
Average rainfall days in September
Harvard, MA
- Average rainfall days in September: 11.1 days
The month with the highest number of rainy days is May (15.3 days).
The months with the least rainy days are January and February (6.5 days).
Average snowfall in September
Harvard, MA
- Average snowfall in September: 0"
The month with the highest snowfall is February (6.14").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Harvard, MA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Harvard, MA
- Average daylight in September: 12h and 30min
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 September: 8h and 12min
The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in September
Harvard, MA
- Average sunshine days in September: 17 days
The month with the most sunshine days is November (17.5 days).
The month with the least sunshine days is April (13.7 days).
Average UV index in September
Harvard, MA
- Average UV index in September: 4
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 September
Harvard, MA
- Average cloud cover in September: 39
The month with the most cloud cover is March (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 35).
Average visibility in September
Harvard, MA
- Average visibility in September: 5mi
The months with the highest visibility are January, March, April, October, November and December (6mi).
The months with the lowest visibility are February, May, June, July, August and September (5mi).





