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 sea temperature 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
In September, West Dennis experiences a minor shift in meteorological conditions with average high-temperatures marked at a refreshing 67.1°F (19.5°C), closely mirroring the climate in August. West Dennis maintains a near steady average temperature of 63°F (17.2°C) during the nights of September, demonstrating little drop from daytime highs.Humidity
In September, the average relative humidity is 79%.Rainfall
In September, the rain falls for 9.5 days. Throughout September, 1.18" (30mm) of precipitation is accumulated. In West Dennis, during the entire year, the rain falls for 129 days and collects up to 14.21" (361mm) of precipitation.Snowfall
In West Dennis, snow does not fall in May through November.Ocean temperature
In West Dennis, the average seawater temperature in September is 64.2°F (17.9°C).Note: The majority of individuals find it unpleasurable to swim in 64.2°F (17.9°C). It becomes progressively harder to manage one's breathing as the water temperature falls below 69.8°F (21°C).
Daylight
In September, the average length of the day is 12h and 28min.On the first day of the month, sunrise is at 6:07 am and sunset at 7:13 pm. On the last day of September, sunrise is at 6:37 am and sunset at 6:23 pm EDT.
Sunshine
In September, the average sunshine is 8.7h.UV index
In West Dennis, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: A typical high UV index of 4 in September suggests the following recommendations:
Adopt protective measures - Suggestions to resist sunburn are offered. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes.
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 ocean temperature in September?
How many hours of daylight does West Dennis have in September?
What time are sunrise and sunset in September?
How many hours of sunshine does West Dennis have in September?
How high is the UV index in September?
Average temperature in September
West Dennis, MA
- Average high temperature in September: 67.1°F
The warmest month (with the highest average high temperature) is August (72.1°F).
The month with the lowest average high temperature is January (38.5°F).
- Average low temperature in September: 63°F
The month with the highest average low temperature is August (68.5°F).
The coldest month (with the lowest average low temperature) is January (30.6°F).
Average pressure in September
West Dennis, MA
- Average pressure in September: 30.05"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 September
West Dennis, MA
- Average wind speed in September: 12.8mph
The windiest month (with the highest average wind speed) is January (16.8mph).
The calmest months (with the lowest average wind speed) are July and August (10.9mph).
Average humidity in September
West Dennis, MA
- Average humidity in September: 79%
The months with the highest relative humidity are June and July (84%).
The month with the lowest relative humidity is November (74%).
Average rainfall in September
West Dennis, MA
- Average rainfall in September: 1.18"
The wettest month (with the highest rainfall) is October (1.93").
The driest month (with the least rainfall) is August (0.94").
Average rainfall days in September
West Dennis, MA
- Average rainfall days in September: 9.5 days
The month with the highest number of rainy days is May (12.5 days).
The month with the least rainy days is February (8.3 days).
Average snowfall in September
West Dennis, MA
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.87").
The months with the least snowfall are May, June, July, August, September, October and November (0").
Average snowfall days in September
West Dennis, MA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average sea temperature in September
West Dennis, MA
- Average sea temperature in September: 64.3°F
The best month for swimming (with the highest average sea temperature) is August (67.5°F).
The coldest month (with the lowest average sea temperature) is March (39°F).
Average daylight in September /
Average sunshine in September
West Dennis, MA
- Average daylight in September: 12h and 3min
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 12min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is August (Average sunshine: 10h and 48min).
The months with the least sunshine are February and December (Average sunshine: 4h and 36min).
Average sunshine days in September
West Dennis, MA
- Average sunshine days in September: 18.6 days
The month with the most sunshine days is September (18.6 days).
The month with the least sunshine days is February (14.3 days).
Average UV index in September
West Dennis, MA
- Average UV index in September: 4
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, November and December (UV index 2).
Average cloud cover in September
West Dennis, MA
- Average cloud cover in September: 31
The month with the most cloud cover is December (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
West Dennis, 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).
West Dennis, Massachusetts, USA
Weather forecast for your location
2. Allow the app to use your location