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
Weather in September
Temperature
A minor adjustment in Siasconset's average high-temperature is noted with the start of September, touching an enjoyable 67.6°F (19.8°C) from August's 72.1°F (22.3°C). An average low-temperature of 63.3°F (17.4°C) is witnessed throughout the month of September, a mere drop from the daytime peak.Humidity
In Siasconset, the average relative humidity in September is 80%.Rainfall
In September, the rain falls for 11.8 days. Throughout September, 2.24" (57mm) of precipitation is accumulated. In Siasconset, during the entire year, the rain falls for 153.1 days and collects up to 26.65" (677mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In Siasconset, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:06 am and sunset at 7:12 pm. On the last day of September, sunrise is at 6:36 am and sunset at 6:22 pm EDT.
Sunshine
In Siasconset, the average sunshine in September is 8.5h.UV index
In Siasconset, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: In September, a daily maximum UV index of 5 leads to the following instructions:
Make use of precautions - Shielding skin and eyes from injury is a requirement. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. 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 are September temperatures?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
What is the average length of the day in September?
When are sunrise and sunset in September?
How many hours of sunshine does Siasconset have in September?
How high is the UV index in September?
Average temperature in September
Siasconset, MA
- Average high temperature in September: 67.6°F
The warmest month (with the highest average high temperature) is August (72.1°F).
The month with the lowest average high temperature is February (39.7°F).
- Average low temperature in September: 63.3°F
The month with the highest average low temperature is August (68.7°F).
The coldest month (with the lowest average low temperature) is February (32.5°F).
Average pressure in September
Siasconset, MA
- Average pressure in September: 30.06"Hg
The months with the highest atmospheric pressure are September and November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Siasconset, MA
- Average wind speed in September: 14.1mph
The windiest month (with the highest average wind speed) is January (18.5mph).
The calmest month (with the lowest average wind speed) is August (11.8mph).
Average humidity in September
Siasconset, MA
- Average humidity in September: 80%
The month with the highest relative humidity is July (86%).
The months with the lowest relative humidity are January, November and December (75%).
Average rainfall in September
Siasconset, MA
- Average rainfall in September: 2.24"
The wettest month (with the highest rainfall) is October (3.27").
The driest month (with the least rainfall) is November (1.77").
Average rainfall days in September
Siasconset, MA
- Average rainfall days in September: 11.8 days
The month with the highest number of rainy days is May (14.3 days).
The month with the least rainy days is February (9.2 days).
Average snowfall in September
Siasconset, MA
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.06").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Siasconset, MA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Siasconset, MA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 8h and 3min
The months with the most sunshine are July and August (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 4h and 18min).
Average sunshine days in September
Siasconset, MA
- Average sunshine days in September: 15.9 days
The month with the most sunshine days is August (16.5 days).
The month with the least sunshine days is January (11.3 days).
Average UV index in September
Siasconset, MA
- Average UV index in September: 5
The months with the highest UV index are July and August (UV index 6).
The months with the lowest UV index are January, February, March and December (UV index 2).
Average cloud cover in September
Siasconset, MA
- Average cloud cover in September: 32
The month with the most cloud cover is December (Cloud cover 54).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Siasconset, MA
- Average visibility in September: 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).
Siasconset, Massachusetts, USA
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