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
As Chatham, New Hampshire, enters September, the average high-temperature subtly lowers from the a moderately hot 75.9°F (24.4°C) of August to an agreeable 68.5°F (20.3°C). Chatham sees an average low-temperature of 47.5°F (8.6°C) during September.Humidity
In Chatham, the average relative humidity in September is 79%.Rainfall
The month with the least rainfall in Chatham is September, when the rain falls for 10.3 days and typically collects 0.94" (24mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September in Chatham is 12h and 30min.On the first day of September, sunrise is at 6:07 am and sunset at 7:19 pm. On the last day of the month, sunrise is at 6:41 am and sunset at 6:26 pm EDT.
Sunshine
In September, the average sunshine in Chatham is 8.6h.UV index
The average daily maximum UV index in September in Chatham is 3. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum UV index of 3 during September leads to these instructions:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. Avoiding the Sun during its peak radiation time around midday is a healthy practice. 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 the temperatures in Chatham in September?
What is the average humidity in September in Chatham?
What is the driest month in Chatham?
How many days does it rain in September in Chatham?
When it does not snow in Chatham?
Does it snow in Chatham in September?
What is the average length of the day in September in Chatham?
When are sunrise and sunset in September in Chatham?
How long on average sun shines in September in Chatham?
How high is the UV index in September in Chatham?
Average temperature in September
Chatham, NH
- Average high temperature in September: 68.5°F
The warmest month (with the highest average high temperature) is July (76.8°F).
The month with the lowest average high temperature is January (24.4°F).
- Average low temperature in September: 47.5°F
The month with the highest average low temperature is July (55.8°F).
The coldest month (with the lowest average low temperature) is January (10.4°F).
Average pressure in September
Chatham, NH
- 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 (29.91"Hg).
Average wind speed in September
Chatham, NH
- Average wind speed in September: 4.4mph
The windiest month (with the highest average wind speed) is January (6.8mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).
Average humidity in September
Chatham, NH
- Average humidity in September: 79%
The month with the highest relative humidity is February (87%).
The months with the lowest relative humidity are May and November (77%).
Average rainfall in September
Chatham, NH
- Average rainfall in September: 0.94"
The wettest months (with the highest rainfall) are April and October (2.17").
The driest month (with the least rainfall) is September (0.94").
Average rainfall days in September
Chatham, NH
- Average rainfall days in September: 10.3 days
The month with the highest number of rainy days is May (15.7 days).
The month with the least rainy days is February (9.8 days).
Average snowfall in September
Chatham, NH
- Average snowfall in September: 0"
The month with the highest snowfall is February (6.73").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Chatham, NH
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (14.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Chatham, NH
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is August (Average sunshine: 10h and 6min).
The month with the least sunshine is February (Average sunshine: 4h and 18min).
Average sunshine days in September
Chatham, NH
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is September (16.5 days).
The month with the least sunshine days is April (10.1 days).
Average UV index in September
Chatham, NH
- Average UV index in September: 3
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).
Average cloud cover in September
Chatham, NH
- Average cloud cover in September: 37
The month with the most cloud cover is February (Cloud cover 53).
The months with the least cloud cover are August and September (Cloud cover 37).
Average visibility in September
Chatham, NH
- Average visibility in September: 4mi
The months with the highest visibility are April, May, June, July, August, October, November and December (5mi).
The months with the lowest visibility are January, February, March and September (4mi).
Chatham, New Hampshire, USA
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