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
Start of September in Londonderry brings a slight shift in the average high-temperature, dipping a bit from August's warm 80.1°F (26.7°C) to an agreeable 72.1°F (22.3°C). An average nighttime temperature of 54°F (12.2°C) is witnessed in Londonderry throughout September.Humidity
In Londonderry, the average relative humidity in September is 77%.Rainfall
In September, in Londonderry, the rain falls for 8.4 days. Throughout September, 0.79" (20mm) of precipitation is accumulated. Throughout the year, there are 104.4 rainfall days, and 12.95" (329mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall in Londonderry.Daylight
The average length of the day in September is 12h and 29min.On the first day of September in Londonderry, sunrise is at 6:10 am and sunset at 7:19 pm. On the last day of the month, sunrise is at 6:42 am and sunset at 6:28 pm EDT.
Sunshine
In September, the average sunshine is 8.4h.UV index
In Londonderry, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the average person.Note: The UV index of 4 during September translates into the following guidance:
Take precautions - Protection against sun damage is advised. Avoid the Sun's strongest UV rays by seeking shade and limiting exposure during midday. Tightly woven clothing, when worn loosely, shields effectively against the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature in Londonderry?
What is the average humidity in September in Londonderry?
How much does it rain in Londonderry in September?
When it does not snow in Londonderry?
Does it snow in Londonderry in September?
What is the average length of the day in September in Londonderry?
What time are sunrise and sunset in September in Londonderry?
How many hours of sunshine does Londonderry have in September?
What is the UV index reading in September in Londonderry?
Average temperature in September
Londonderry, NH
- Average high temperature in September: 72.1°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in September: 54°F
The month with the highest average low temperature is July (61°F).
The coldest month (with the lowest average low temperature) is January (18°F).
Average pressure in September
Londonderry, 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 (29.92"Hg).
Average wind speed in September
Londonderry, NH
- Average wind speed in September: 5.5mph
The windiest month (with the highest average wind speed) is January (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
Londonderry, NH
- Average humidity in September: 77%
The month with the highest relative humidity is February (81%).
The month with the lowest relative humidity is April (72%).
Average rainfall in September
Londonderry, NH
- Average rainfall in September: 0.79"
The wettest month (with the highest rainfall) is October (1.38").
The driest month (with the least rainfall) is January (0.75").
Average rainfall days in September
Londonderry, NH
- Average rainfall days in September: 8.4 days
The month with the highest number of rainy days is June (12.1 days).
The month with the least rainy days is January (4.1 days).
Average snowfall in September
Londonderry, NH
- Average snowfall in September: 0"
The month with the highest snowfall is December (2.99").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Londonderry, NH
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (7.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Londonderry, NH
- 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 2min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in September
Londonderry, NH
- Average sunshine days in September: 20 days
The months with the most sunshine days are January and December (21.3 days).
The month with the least sunshine days is June (16.7 days).
Average UV index in September
Londonderry, NH
- Average UV index in September: 4
The months with the highest UV index are June, 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
Londonderry, NH
- Average cloud cover in September: 37
The month with the most cloud cover is March (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in September
Londonderry, NH
- Average visibility in September: 5mi
The months with the highest visibility are January, April, November and December (6mi).
The months with the lowest visibility are February, March, May, June, July, August, September and October (5mi).
Londonderry, New Hampshire, USA
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