Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
September
Weather in September
Temperature
Boston's weather subtly changes with the onset of September, barely falling from a warm 75.9°F (24.4°C) in August to an agreeable 70°F (21.1°C). September brings an average low-temperature of 52.7°F (11.5°C) to Boston.Humidity
In Boston, the average relative humidity in September is 80%.Rainfall
The month with the least rainfall is September, when the rain falls for 13.6 days and typically collects 1.22" (31mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In Boston, the average length of the day in September is 12h and 29min.On the first day of the month, sunrise is at 6:40 am and sunset at 7:48 pm. On the last day of September, sunrise is at 7:11 am and sunset at 6:57 pm EDT.
Sunshine
In Boston, the average sunshine in September is 8.8h.UV index
In Boston, the average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: A daily high UV index of 3 in September leads to these guidelines:
Take precautions - Protection against sunburn is recommended. UV radiation is strongest from the Sun during midday; protect yourself by staying in shaded areas. Experience reduced UV exposure by about half when donning a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
What is the driest month?
How many days does it rain in September?
When it does not snow?
Does it snow in September?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Boston have in September?
How high is the UV index in September?
Average temperature in September
Boston, NY
- Average high temperature in September: 70°F
The warmest month (with the highest average high temperature) is July (77.2°F).
The month with the lowest average high temperature is January (27.9°F).
- Average low temperature in September: 52.7°F
The month with the highest average low temperature is July (59.5°F).
The coldest month (with the lowest average low temperature) is January (17.4°F).
Average pressure in September
Boston, NY
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Boston, NY
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is January (11.1mph).
The calmest months (with the lowest average wind speed) are July and August (6.6mph).
Average humidity in September
Boston, NY
- Average humidity in September: 80%
The months with the highest relative humidity are January and February (88%).
The month with the lowest relative humidity is May (79%).
Average rainfall in September
Boston, NY
- Average rainfall in September: 1.22"
The wettest month (with the highest rainfall) is May (2.13").
The driest month (with the least rainfall) is September (1.22").
Average rainfall days in September
Boston, NY
- Average rainfall days in September: 13.6 days
The month with the highest number of rainy days is October (17.2 days).
The month with the least rainy days is February (5.8 days).
Average snowfall in September
Boston, NY
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.61").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Boston, NY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (16.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Boston, NY
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 5min
The months with the most sunshine are July and August (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 2h and 18min).
Average sunshine days in September
Boston, NY
- Average sunshine days in September: 14 days
The month with the most sunshine days is September (14 days).
The month with the least sunshine days is January (8.6 days).
Average UV index in September
Boston, NY
- Average UV index in September: 3
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January, February and December (UV index 1).
Average cloud cover in September
Boston, NY
- Average cloud cover in September: 37
The month with the most cloud cover is January (Cloud cover 78).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in September
Boston, NY
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February, March and December (5mi).