September weather forecast and climate
Griggstown, NJ

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

Temperature

In Griggstown, New Jersey, the average high-temperature in September marginally drops, from a moderately hot 82.9°F (28.3°C) in August, to a still warm 75.7°F (24.3°C). In September, the average low-temperature is 59°F (15°C).

Humidity

The average relative humidity in September is 77%.

Rainfall

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

Snowfall

In Griggstown snow does not fall in June through October.

Daylight

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

Sunshine

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

UV index

In Griggstown, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from unprotected exposure to the Sun's UV rays for the average person.
Note: In September, the average maximum UV index of 4 translate into the following recommendations:
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. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.

What is the temperature in September in Griggstown?

In Griggstown, New Jersey, in September, the average high-temperature is 75.7°F (24.3°C), and the average low-temperature is 59°F (15°C).

What is the average humidity in September in Griggstown?

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

How much does it rain in Griggstown in September?

In Griggstown, New Jersey, in September, it is raining for 10 days, with typically 0.67" (17mm) of accumulated precipitation.

What is the driest month in Griggstown?

The month with the least rainfall in Griggstown is September when the rain falls for 10 days and typically collects 0.67" (17mm) of precipitation.

When it does not snow in Griggstown?

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

How many hours of daylight does Griggstown have in September?

In Griggstown, New Jersey, the average length of the day in September 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?

In Griggstown, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium hazard to health from unsafe exposure to the Sun's UV rays.
Average temperature in September - Griggstown, NJ
  • Average high temperature in September: 75.7°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 (36.9°F).

  • Average low temperature in September: 59°F

The month with the highest average low temperature is July (66.9°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).

Average pressure in September - Griggstown, NJ
  • Average pressure in September: 30.05"

The month with the highest atmospheric pressure is November (30.11").
The month with the lowest atmospheric pressure is June (29.93").

Average wind speed in September - Griggstown, NJ
  • Average wind speed in September: 6mph

The windiest month (with the highest average wind speed) is March (8.8mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).

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: 0.67"

The wettest month (with the highest rainfall) is July (1.69").
The driest month (with the least rainfall) is September (0.67").

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: 0"

The month with the highest snowfall is March (1.42").
Months with the least snowfall are June, July, August, September and October (0").

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: 6mi

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).