September weather forecastRockleigh, NJ

September

Weather in September

The first month of the autumn, September, is still a warm month in Rockleigh, New Jersey, with temperature in the range of an average low of 59.9°F (15.5°C) and an average high of 75.4°F (24.1°C).

Temperature

The start of September involves a subtle temperature drop, shifting from a moderately hot 82.9°F (28.3°C) in August to a still warm 75.4°F (24.1°C). The average low-temperature during September nights is a mild 59.9°F (15.5°C).

Humidity

The average relative humidity in September is 73%.

Rainfall

September is the month with the least rainfall. Rain falls for 11.6 days and accumulates 1.73" (44mm) of precipitation.

Snowfall

In Rockleigh, snow does not fall in May through October.

Daylight

In September, the average length of the day is 12h and 28min.
On the first day of September, sunrise is at 6:23 am and sunset at 7:27 pm. On the last day of the month, sunrise is at 6:52 am and sunset at 6:38 pm EDT.

Sunshine

The average sunshine in September is 8.6h.

UV index

In Rockleigh, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for average individuals.
Note: The UV index of 4 in September translates into these instructions:
Act with care - The need to guard against sun damage is communicated. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Enhance your sun protection with tightly woven, yet airy clothing.

Frequently asked questions

Rockleigh in September has an average high-temperature of 75.4°F (24.1°C) and an average low-temperature of 59.9°F (15.5°C). The average heat index (a.k.a. 'feels like', 'felt air temperature'), which factors the actual air temperature with the relative humidity, in August is estimated at 87.8°F (31°C).

In September, the average relative humidity is 73%.

September is the month with the least rainfall in Rockleigh. Rain falls for 11.6 days and accumulates 1.73" (44mm) of precipitation.

In Rockleigh, in September, during 11.6 rainfall days, 1.73" (44mm) of precipitation is typically accumulated.

May through October are months without snowfall.

In September, the average day length is 12h and 28min.

On the first day of September, sunrise is at 6:23 am and sunset at 7:27 pm. On the last day of the month, sunrise is at 6:52 am and sunset at 6:38 pm EDT.

In September, the average sunshine duration is 8.6h.

In Rockleigh, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium hazard to health from exposure to the Sun's UV radiation.
Average high temperature
Average low temperature
Average pressure
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average snowfall
Average snowfall days
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Rockleigh, NJ

  • Average high temperature in September: 75.4°F

The warmest month (with the highest average high temperature) is July (84.9°F).
The month with the lowest average high temperature is January (35.4°F).

  • Average low temperature in September: 59.9°F

The month with the highest average low temperature is July (68°F).
The coldest month (with the lowest average low temperature) is January (24.1°F).

Average pressure in September
Rockleigh, 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
Rockleigh, NJ

  • Average wind speed in September: 6.3mph

The windiest months (with the highest average wind speed) are January and March (8.5mph).
The calmest months (with the lowest average wind speed) are July and August (5.8mph).

Average humidity in September
Rockleigh, NJ

  • Average humidity in September: 73%

The month with the highest relative humidity is February (77%).
The month with the lowest relative humidity is August (68%).

Average rainfall in September
Rockleigh, NJ

  • Average rainfall in September: 1.73"

The wettest month (with the highest rainfall) is December (3.46").
The driest month (with the least rainfall) is September (1.73").

Average rainfall days in September
Rockleigh, NJ

  • Average rainfall days in September: 11.6 days

The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is January (8.2 days).

Average snowfall in September
Rockleigh, NJ

  • Average snowfall in September: 0"

The month with the highest snowfall is March (3.07").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in September
Rockleigh, NJ

  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (6.9 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

Average daylight in September /
Average sunshine in September
Rockleigh, 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 36min

The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).

Average sunshine days in September
Rockleigh, NJ

  • Average sunshine days in September: 16.7 days

The months with the most sunshine days are January and November (18.1 days).
The months with the least sunshine days are April and June (12.7 days).

Average UV index in September
Rockleigh, 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
Rockleigh, NJ

  • Average cloud cover in September: 37

The months with the most cloud cover are February, March and December (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 32).

Average visibility in September
Rockleigh, 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).