September weather forecast and climate
Griggstown, NJ

September, the first month of the autumn, in Griggstown, is still a warm month, with average temperature varying between 75.7°F (24.3°C) and 59°F (15°C).

Temperature

In September, the average high-temperature slightly decreases, from 82.9°F (28.3°C) in August, to a still warm 75.7°F (24.3°C). In Griggstown, the average low-temperature is 59°F (15°C).

Humidity

The average relative humidity in Griggstown is 77%.

Rainfall

September is the month with the least rainfall. Rain falls for 10 days and accumulates 0.67" (17mm) of precipitation.

Snowfall

In Griggstown, New Jersey, snow does not fall in June through October.

Daylight

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

Sunshine

In Griggstown, the average sunshine is 8.8h.

UV index

In Griggstown, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from the exposure to the Sun's UV rays for the average person.
Note: The average daily UV index of 4 in September transform into the following instructions:
Take precautions - Protection against the skin and eye damage is obliged. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun.

What is the temperature in September in Griggstown?

The average high-temperature, in September, in Griggstown, is 75.7°F (24.3°C), while the average low-temperature is 59°F (15°C).

What is the average humidity in September in Griggstown?

In September, the average relative humidity in Griggstown, New Jersey, is 77%.

How many days does it rain in September in Griggstown?

In September, the rain falls for 10 days. Throughout September, 0.67" (17mm) of precipitation is accumulated.

What is the driest month in Griggstown?

September is the month with the least rainfall in Griggstown, New Jersey. Rain falls for 10 days and accumulates 0.67" (17mm) of precipitation.

When it does not snow in Griggstown?

In Griggstown snow does not fall in June through October.

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

The average length of the day in September in Griggstown is 12.4h.

How long on average sun shines in September in Griggstown?

In September, the average sunshine in Griggstown, New Jersey, is 8.8h.

How high is the UV index in September in Griggstown?

The average daily maximum UV index in September in Griggstown, New Jersey, is 4. A UV Index estimate of 3 to 5 represents a medium hazard to health from the exposure to the Sun's UV radiation.
Average temperature in September - Griggstown, NJ
  • Average high temperature in September: 24.3°C

The warmest month (with the highest average high temperature) is July (29.3°C).
The month with the lowest average high temperature is January (2.7°C).

  • Average low temperature in September: 15°C

The month with the highest average low temperature is July (19.4°C).
The coldest month (with the lowest average low temperature) is January (-4.3°C).

Average pressure in September - Griggstown, NJ
  • Average pressure in September: 1017.7mbar

The month with the highest atmospheric pressure is November (1019.7mbar).
The month with the lowest atmospheric pressure is June (1013.7mbar).

Average wind speed in September - Griggstown, NJ
  • Average wind speed in September: 9.6km/h

The windiest month (with the highest average wind speed) is March (14.1km/h).
The calmest month (with the lowest average wind speed) is August (8.7km/h).

Average humidity in September - Griggstown, NJ
  • Average humidity in September: 77%

The month with the highest relative humidity is October (79%).
The month with the lowest relative humidity is April (73%).

Average rainfall in September - Griggstown, NJ
  • Average rainfall in September: 17mm

The wettest month (with the highest rainfall) is July (43mm).
The driest month (with the least rainfall) is September (17mm).

Average rainfall days in September - Griggstown, NJ
  • Average rainfall days in September: 10 days

The month with the highest number of rainy days is July (13.9 days).
The month with the least rainy days is January (6.1 days).

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

The month with the highest snowfall is March (36mm).
Months with the least snowfall are June, July, August, September and October (0mm).

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

The month with the highest number of snowfall days is January (4.6 days).
Months with the least snowfall days are June, July, August, September and October (0 days).

Average daylight in September / Average sunshine in September - Griggstown, 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: 8.8h

The month with the most sunshine is July (Average sunshine: 10.5h).
The month with the least sunshine is February (Average sunshine: 4.8h).

Average sunshine days in September - Griggstown, NJ
  • Average sunshine days in September: 17.2 days

The month with the most sunshine days is January (21.8 days).
The month with the least sunshine days is July (13.3 days).

Average UV index in September - Griggstown, NJ
  • Average UV index in September: 4

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

Average cloud cover in September - Griggstown, NJ
  • Average cloud cover in September: 38

Months with the most cloud cover are February, March and December (Cloud cover 47).
Months with the least cloud cover are July and August (Cloud cover 33).

Average visibility in September - Griggstown, NJ
  • Average visibility in September: 9km

Months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (9km).
The month with the lowest visibility is May (8km).