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
With the arrival of September, Iselin notices a mild change in the average high-temperature, sliding from August's moderately hot 81.9°F (27.7°C) to a still warm 75.2°F (24°C). Iselin's average low-temperature for the month of September records at an enjoyable 61.2°F (16.2°C).Humidity
In September, the average relative humidity is 75%.Rainfall
September is the month with the least rainfall. Rain falls for 9.6 days and accumulates 0.39" (10mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
The average length of the day in September in Iselin is 12h and 27min.On the first day of the month, sunrise is at 6:25 am and sunset at 7:28 pm. On the last day of September, sunrise is at 6:53 am and sunset at 6:40 pm EDT.
Sunshine
In Iselin, the average sunshine in September is 8.9h.UV index
In Iselin, the average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: A maximum high UV index of 5 in September translates into the following recommendations:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. To cut down UV radiation exposure by about half, sport a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Iselin in September?
What is the average humidity in September in Iselin?
What is the driest month in Iselin?
How much does it rain in Iselin in September?
When it does not snow in Iselin?
How many hours of daylight does Iselin have in September?
What time are sunrise and sunset in September in Iselin?
How many hours of sunshine does Iselin have in September?
What is the UV index intensity in September in Iselin?
Average temperature in September
Iselin, NJ
- Average high temperature in September: 75.2°F
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (36.5°F).
- Average low temperature in September: 61.2°F
The month with the highest average low temperature is July (68.9°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in September
Iselin, NJ
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Iselin, NJ
- Average wind speed in September: 7mph
The windiest months (with the highest average wind speed) are January and March (9.6mph).
The calmest month (with the lowest average wind speed) is July (6.3mph).
Average humidity in September
Iselin, NJ
- Average humidity in September: 75%
The month with the highest relative humidity is February (77%).
The month with the lowest relative humidity is August (72%).
Average rainfall in September
Iselin, NJ
- Average rainfall in September: 0.39"
The wettest month (with the highest rainfall) is July (1.22").
The driest month (with the least rainfall) is September (0.39").
Average rainfall days in September
Iselin, NJ
- Average rainfall days in September: 9.6 days
The month with the highest number of rainy days is July (12.7 days).
The month with the least rainy days is January (4.9 days).
Average snowfall in September
Iselin, NJ
- Average snowfall in September: 0"
The month with the highest snowfall is March (0.83").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Iselin, NJ
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (4.2 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
Iselin, NJ
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 8h and 5min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in September
Iselin, NJ
- Average sunshine days in September: 17.9 days
The month with the most sunshine days is January (22.6 days).
The month with the least sunshine days is July (14.8 days).
Average UV index in September
Iselin, NJ
- Average UV index in September: 5
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
Iselin, NJ
- Average cloud cover in September: 35
The months with the most cloud cover are February, March and December (Cloud cover 47).
The months with the least cloud cover are July and August (Cloud cover 30).
Average visibility in September
Iselin, NJ
- 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).
Iselin, New Jersey, USA
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