September weather forecastAllendale, NJ
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Allendale, New Jersey, with an average temperature fluctuating between 75.2°F (24°C) and 58.3°F (14.6°C).Temperature
The transition into September is accompanied by a slight temperature decrease, with the average high-temperature shifting from a warm 82.9°F (28.3°C) in August to a still moderately hot 75.2°F (24°C). In Allendale, the September nights cool down to an average low of 58.3°F (14.6°C).Humidity
In Allendale, the average relative humidity in September is 74%.Rainfall
September is the month with the least rainfall. Rain falls for 12.9 days and accumulates 1.89" (48mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In Allendale, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:23 am and sunset at 7:28 pm. On the last day of September, sunrise is at 6:52 am and sunset at 6:39 pm EDT.
Sunshine
In September, the average sunshine is 8.5h.UV index
The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: The UV index of 4 in September translates into these instructions:
Exercise caution. Those with pale skin may experience burns in less than half an hour. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Allendale, NJ
- Average high temperature in September: 75.2°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (35.2°F).
- Average low temperature in September: 58.3°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).
Average pressure in September
Allendale, NJ
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Allendale, NJ
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is March (8mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in September
Allendale, NJ
- Average humidity in September: 74%
The months with the highest relative humidity are February and December (78%).
The month with the lowest relative humidity is August (70%).
Average rainfall in September
Allendale, NJ
- Average rainfall in September: 1.89"
The wettest month (with the highest rainfall) is December (3.58").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in September
Allendale, NJ
- Average rainfall days in September: 12.9 days
The months with the highest number of rainy days are May and July (16.8 days).
The month with the least rainy days is January (8.4 days).
Average snowfall in September
Allendale, NJ
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.09").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Allendale, NJ
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (7.9 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Allendale, NJ
- Average daylight in September: 12h and 30min
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 30min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in September
Allendale, NJ
- Average sunshine days in September: 15.1 days
The month with the most sunshine days is November (18.7 days).
The month with the least sunshine days is June (11.5 days).
Average UV index in September
Allendale, NJ
- 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
Allendale, NJ
- Average cloud cover in September: 39
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in September
Allendale, NJ
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).
