September weather forecast and climate
Walnut Creek, NC

The first month of the autumn, September, is still a warm month in Walnut Creek, North Carolina, with average temperature varying between 81.5°F (27.5°C) and 65.3°F (18.5°C).

Temperature

In September, the average high-temperature slightly decreases, from a hot 86.9°F (30.5°C) in August, to a moderately hot 81.5°F (27.5°C). The average low-temperature, in September, is 65.3°F (18.5°C).

Heat index

In September, the average heat index is appraised at a hot 87.4°F (30.8°C). Constant exposure and activity lead to possible fatigue. Prolonged exercise may result in heat cramps.
Take into consideration that the heat index values are calculated for shade and light wind conditions. With the exposure to direct sunlight, the heat index may be increased by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like', 'real feel', 'apparent temperature', or 'felt air temperature', is a calculated temperature value of how hot it feels when the moisture in the air is factored in. Additional factors like wind, clothing, pregnancy, and activity influence one's weather impression. Be aware that direct exposure to sunlight increases heat impact, and may raise the heat index additionally, by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it is vital to remain hydrated, particularly during prolonged physical activities.

Humidity

Months with the highest humidity are August and September, with an average relative humidity of 79%.

Rainfall

In Walnut Creek, during September, the rain falls for 9 days and regularly aggregates up to 0.79" (20mm) of precipitation. In Walnut Creek, North Carolina, during the entire year, the rain falls for 110.7 days and collects up to 9.02" (229mm) of precipitation.

Snowfall

March through December are months without snowfall in Walnut Creek.

Daylight

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

Sunshine

In Walnut Creek, the average sunshine is 9.1h.

UV index

In September, the average daily maximum UV index in Walnut Creek is 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unprotected exposure to the Sun's UV rays for average individuals.
Note: The average daily UV index of 5 in September transform into the following instructions:
Take precautions. Light skin individuals may get burned in less than 30 minutes. 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 Walnut Creek?

The average high-temperature, in September, in Walnut Creek, North Carolina, is 81.5°F (27.5°C), while the average low-temperature is 65.3°F (18.5°C). The average heat index (a.k.a. 'apparent temperature', 'feels like'), that factores the actual air temperature with the relative humidity, in September is appraised at 87.4°F (30.8°C).

What are the most humid months in Walnut Creek?

Months with the highest humidity in Walnut Creek, North Carolina, are August and September, with an average relative humidity of 79%.

What is the average humidity in September in Walnut Creek?

In Walnut Creek, North Carolina, the average relative humidity in September is 79%.

How much does it rain in Walnut Creek in September?

In September, in Walnut Creek, North Carolina, the rain falls for 9 days. Throughout September, 0.79" (20mm) of precipitation is accumulated.

When it does not snow in Walnut Creek?

March through December are months without snowfall in Walnut Creek.

How many hours of daylight does Walnut Creek have in September?

In Walnut Creek, North Carolina, the average length of the day in September is 12.4h.

How many hours of sunshine does Walnut Creek have in September?

The average sunshine in September in Walnut Creek is 9.1h.

What is the UV index reading in September in Walnut Creek?

The average daily maximum UV index in September in Walnut Creek is 5. A UV Index of 3 to 5 symbolizes a medium health risk from unprotected exposure to the UV radiation.
Average temperature in September - Walnut Creek, NC
  • Average high temperature in September: 27.5°C

The warmest month (with the highest average high temperature) is July (31.3°C).
The month with the lowest average high temperature is January (9.8°C).

  • Average low temperature in September: 18.5°C

The month with the highest average low temperature is July (22°C).
The coldest month (with the lowest average low temperature) is January (1.4°C).

Average pressure in September - Walnut Creek, NC
  • Average pressure in September: 1016.5mbar

The month with the highest atmospheric pressure is November (1020.5mbar).
The month with the lowest atmospheric pressure is June (1014.6mbar).

Average wind speed in September - Walnut Creek, NC
  • Average wind speed in September: 10.6km/h

The windiest month (with the highest average wind speed) is April (13.9km/h).
The calmest month (with the lowest average wind speed) is August (9km/h).

Average humidity in September - Walnut Creek, NC
  • Average humidity in September: 79%

Months with the highest relative humidity are August and September (79%).
The month with the lowest relative humidity is January (73%).

Average rainfall in September - Walnut Creek, NC
  • Average rainfall in September: 20mm

The wettest month (with the highest rainfall) is August (36mm).
The driest month (with the least rainfall) is January (10mm).

Average rainfall days in September - Walnut Creek, NC
  • Average rainfall days in September: 9 days

The month with the highest number of rainy days is August (15 days).
The month with the least rainy days is November (5.8 days).

Average snowfall in September - Walnut Creek, NC
  • Average snowfall in September: 0mm

The month with the highest snowfall is February (2mm).
Months with the least snowfall are March, April, May, June, July, August, September, October, November and December (0mm).

Average snowfall days in September - Walnut Creek, NC
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (0.7 days).
Months with the least snowfall days are April, May, June, July, August, September and October (0 days).

Average daylight in September / Average sunshine in September - Walnut Creek, NC
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 14.5h).
The month with the shortest days is December (Average daylight: 9.8h).

  • 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 December (Average sunshine: 5.5h).

Average sunshine days in September - Walnut Creek, NC
  • Average sunshine days in September: 18 days

The month with the most sunshine days is October (23.5 days).
The month with the least sunshine days is June (11.3 days).

Average UV index in September - Walnut Creek, NC
  • Average UV index in September: 5

Months with the highest UV index are June and July (UV index 7).
The month with the lowest UV index is January (UV index 2).

Average cloud cover in September - Walnut Creek, NC
  • Average cloud cover in September: 36

Months with the most cloud cover are February and March (Cloud cover 41).
Months with the least cloud cover are June, July and October (Cloud cover 32).

Average visibility in September - Walnut Creek, NC
  • Average visibility in September: 9km

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