September weather forecast and climate
Holmdel, NJ

September, the first month of the autumn, in Holmdel, is also a moderately hot month, with average temperature ranging between max 74.1°F (23.4°C) and min 63.5°F (17.5°C).

Temperature

In September, the average high-temperature slightly decreases, from 80.2°F (26.8°C) in August, to a still moderately hot 74.1°F (23.4°C). In September, in Holmdel, the average low-temperature is 63.5°F (17.5°C).

Humidity

In September, the average relative humidity is 76%.

Rainfall

September is the month with the least rainfall. Rain falls for 6 days and accumulates 0.12" (3mm) of precipitation.

Snowfall

In Holmdel snow does not fall in April through November.

Daylight

In September, the average length of the day is 12.4h.

Sunshine

In September, the average sunshine is 9.1h.

UV index

The average daily maximum UV index in Holmdel, New Jersey, is 5. A UV Index estimate of 3 to 5 represents a moderate health risk from the exposure to the Sun's UV rays for ordinary individuals.
Note: The daily maximum UV index of 5 in September interpret into the following advice:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.

What is the temperature in September in Holmdel?

In Holmdel, New Jersey, in September, the average high-temperature is 74.1°F (23.4°C), and the average low-temperature is 63.5°F (17.5°C).

What is the average humidity in September in Holmdel?

In Holmdel, New Jersey, the average relative humidity in September is 76%.

How much does it rain in Holmdel in September?

In September, in Holmdel, the rain falls for 6 days. Throughout September, 0.12" (3mm) of precipitation is accumulated.

What is the driest month in Holmdel?

September is the month with the least rainfall in Holmdel. Rain falls for 6 days and accumulates 0.12" (3mm) of precipitation.

When it does not snow in Holmdel?

April through November are months without snowfall.

What is the average length of the day in September in Holmdel?

The average length of the day in September in Holmdel, New Jersey, is 12.4h.

How many hours of sunshine does Holmdel have in September?

In September, the average sunshine in Holmdel, New Jersey, is 9.1h.

What is the UV index reading in September in Holmdel?

In September, the average daily maximum UV index in Holmdel is 5. A UV Index of 3 to 5 symbolizes a medium hazard to health from unsafe exposure to the Sun's UV rays.
Average temperature in September - Holmdel, NJ
  • Average high temperature in September: 23.4°C

The warmest month (with the highest average high temperature) is July (27.6°C).
The month with the lowest average high temperature is January (3.2°C).

  • Average low temperature in September: 17.5°C

The month with the highest average low temperature is July (21°C).
The coldest month (with the lowest average low temperature) is January (-2.6°C).

Average pressure in September - Holmdel, NJ
  • Average pressure in September: 1017.6mbar

The month with the highest atmospheric pressure is November (1019.5mbar).
The month with the lowest atmospheric pressure is June (1013.7mbar).

Average wind speed in September - Holmdel, NJ
  • Average wind speed in September: 13.1km/h

The windiest month (with the highest average wind speed) is January (17.9km/h).
The calmest month (with the lowest average wind speed) is July (11.5km/h).

Average humidity in September - Holmdel, NJ
  • Average humidity in September: 76%

Months with the highest relative humidity are May and June (78%).
The month with the lowest relative humidity is November (73%).

Average rainfall in September - Holmdel, NJ
  • Average rainfall in September: 3mm

The wettest month (with the highest rainfall) is July (18mm).
The driest month (with the least rainfall) is September (3mm).

Average rainfall days in September - Holmdel, NJ
  • Average rainfall days in September: 6 days

The month with the highest number of rainy days is July (8 days).
The month with the least rainy days is January (3.4 days).

Average snowfall in September - Holmdel, NJ
  • Average snowfall in September: 0mm

The month with the highest snowfall is January (4mm).
Months with the least snowfall are April, May, June, July, August, September, October and November (0mm).

Average snowfall days in September - Holmdel, NJ
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (2.6 days).
Months with the least snowfall days are April, May, June, July, August, September, October and November (0 days).

Average daylight in September / Average sunshine in September - Holmdel, NJ
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 15h).
The month with the shortest days is December (Average daylight: 9.3h).

  • Average sunshine in September: 9.1h

The month with the most sunshine is July (Average sunshine: 10.8h).
The month with the least sunshine is February (Average sunshine: 4.9h).

Average sunshine days in September - Holmdel, NJ
  • Average sunshine days in September: 22.1 days

The month with the most sunshine days is January (25.7 days).
The month with the least sunshine days is July (17.3 days).

Average UV index in September - Holmdel, NJ
  • Average UV index in September: 5

Months with the highest UV index are June, July and August (UV index 6).
Months with the lowest UV index are January, February, November and December (UV index 2).

Average cloud cover in September - Holmdel, NJ
  • Average cloud cover in September: 33

Months with the most cloud cover are February, March and December (Cloud cover 46).
Months with the least cloud cover are July and August (Cloud cover 28).

Average visibility in September - Holmdel, NJ
  • Average visibility in September: 10km

Months with the highest visibility are January, February, March, April, July, August, September, October, November and December (10km).
Months with the lowest visibility are May and June (9km).