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
In Grantham, entering September brings a subtle temperature decrement, reducing from August's moderately hot 76.6°F (24.8°C) to an agreeable 68.9°F (20.5°C). In the month of September, an average of 49.3°F (9.6°C) marks the low-temperature in Grantham, New Hampshire.Humidity
The average relative humidity in September is 80%.Rainfall
September is the month with the least rainfall. Rain falls for 11.5 days and accumulates 2.05" (52mm) of precipitation.Snowfall
June through September are months without snowfall in Grantham, New Hampshire.Daylight
In September, the average length of the day is 12h and 29min.On the first day of September in Grantham, sunrise is at 6:13 am and sunset at 7:23 pm. On the last day of the month, sunrise is at 6:45 am and sunset at 6:30 pm EDT.
Sunshine
In Grantham, the average sunshine in September is 8.2h.UV index
In Grantham, the average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for ordinary individuals.Note: In September, the maximum UV index of 3 transforms into these recommendations:
Exercise prevention - Warding off sunburn is urged. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized.
Frequently asked questions
What is the usual temperature for Grantham in September?
What is the average humidity in September in Grantham?
What is the driest month in Grantham?
How much does it rain in Grantham in September?
When it does not snow in Grantham?
Does it snow in Grantham in September?
What is the average length of the day in September in Grantham?
When are sunrise and sunset in September in Grantham?
How many hours of sunshine does Grantham have in September?
What is the UV index reading in September in Grantham?
Average temperature in September
Grantham, NH
- Average high temperature in September: 68.9°F
The warmest month (with the highest average high temperature) is July (78.8°F).
The month with the lowest average high temperature is January (25.9°F).
- Average low temperature in September: 49.3°F
The month with the highest average low temperature is July (57.2°F).
The coldest month (with the lowest average low temperature) is January (13.3°F).
Average pressure in September
Grantham, NH
- 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 (29.91"Hg).
Average wind speed in September
Grantham, NH
- Average wind speed in September: 5.2mph
The windiest months (with the highest average wind speed) are January, February, March and April (7.6mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in September
Grantham, NH
- Average humidity in September: 80%
The months with the highest relative humidity are January and February (86%).
The month with the lowest relative humidity is April (75%).
Average rainfall in September
Grantham, NH
- Average rainfall in September: 2.05"
The wettest month (with the highest rainfall) is October (3.39").
The driest month (with the least rainfall) is September (2.05").
Average rainfall days in September
Grantham, NH
- Average rainfall days in September: 11.5 days
The month with the highest number of rainy days is June (16.8 days).
The month with the least rainy days is February (7.9 days).
Average snowfall in September
Grantham, NH
- Average snowfall in September: 0"
The month with the highest snowfall is February (11.18").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Grantham, NH
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (14.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Grantham, NH
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 8h and 1min
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 0min).
Average sunshine days in September
Grantham, NH
- Average sunshine days in September: 16.8 days
The month with the most sunshine days is September (16.8 days).
The month with the least sunshine days is February (11.3 days).
Average UV index in September
Grantham, NH
- 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 February and December (UV index 1).
Average cloud cover in September
Grantham, NH
- Average cloud cover in September: 40
The month with the most cloud cover is February (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 36).
Average visibility in September
Grantham, NH
- Average visibility in September: 5mi
The months with the highest visibility are January, March, April, May, June, July, August, September, October, November and December (5mi).
The month with the lowest visibility is February (4mi).
Grantham, New Hampshire, USA
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