September weather forecast
Herculaneum, MO

englishespañol中文
Share

Weather in September

September, the first month of the autumn in Herculaneum, is also a moderately hot month, with an average temperature fluctuating between 79.7°F (26.5°C) and 59.9°F (15.5°C).

Temperature

The arrival of September is marked by a minor reduction in average high-temperature, sliding from a hot 86.2°F (30.1°C) in August to a warm 79.7°F (26.5°C). September brings with it a nighttime average temperature of 59.9°F (15.5°C).

Humidity

The average relative humidity in September is 74%.

Rainfall

In Herculaneum, during September, the rain falls for 13 days and regularly aggregates up to 2.13" (54mm) of precipitation. Throughout the year, in Herculaneum, there are 155 rainfall days, and 34.92" (887mm) of precipitation is accumulated.

Snowfall

In Herculaneum, snow does not fall in April through October.

Daylight

In Herculaneum, the average length of the day in September is 12h and 25min.
On the first day of September, sunrise is at 6:31 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:57 am and sunset at 6:45 pm CDT.

Sunshine

In Herculaneum, the average sunshine in September is 9.5h.

UV index

In September, the average daily maximum UV index is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: A maximum daily UV index of 5 during September morphs into the following directions:
Guard yourself - An obligation to protect skin and eyes from harm exists. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. 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.
[Resources]

Frequently asked questions

What are the temperatures in Herculaneum in September?

The high-temperature, in September, in Herculaneum, is 79.7°F (26.5°C), while the low-temperature averages to 59.9°F (15.5°C). In August, the average heat index (a.k.a. 'felt air temperature', 'apparent temperature'), which combines air temperature and relative humidity, is calculated to be 98.6°F (37°C).

What is the average humidity in September in Herculaneum?

In Herculaneum, the average relative humidity in September is 74%.

How much does it rain in Herculaneum in September?

In Herculaneum, Missouri, in September, during 13 rainfall days, 2.13" (54mm) of precipitation is typically accumulated.

When it does not snow in Herculaneum?

In Herculaneum, snow does not fall in April through October.

How many hours of daylight does Herculaneum have in September?

In September, the average day length in Herculaneum, Missouri, is 12h and 25min.

When is the sunrise / sunset in September in Herculaneum?

On the first day of September in Herculaneum, sunrise is at 6:31 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:57 am and sunset at 6:45 pm CDT.

How long on average sun shines in September in Herculaneum?

In Herculaneum, the average sunshine duration in September is 9.5h.

How high is the UV index in September in Herculaneum?

In September, the average daily maximum UV index in Herculaneum, Missouri, is 5. A UV Index of 3 to 5 symbolizes a moderate vulnerability from exposure to the Sun's UV radiation.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Herculaneum, MO

Average temperature in September - Herculaneum, MO
  • Average high temperature in September: 79.7°F

The warmest month (with the highest average high temperature) is July (88°F).
The month with the lowest average high temperature is January (39°F).

  • Average low temperature in September: 59.9°F

The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).

[Resources]

Average pressure in September
Herculaneum, MO

Average pressure in September - Herculaneum, MO
  • Average pressure in September: 30.02"Hg

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

[Resources]

Average wind speed in September
Herculaneum, MO

Average wind speed in September - Herculaneum, MO
  • Average wind speed in September: 5.6mph

The windiest month (with the highest average wind speed) is January (9mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).

[Resources]

Average humidity in September
Herculaneum, MO

Average humidity in September - Herculaneum, MO
  • Average humidity in September: 74%

The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (72%).

[Resources]

Average rainfall in September
Herculaneum, MO

Average rainfall in September - Herculaneum, MO
  • Average rainfall in September: 2.13"

The wettest month (with the highest rainfall) is May (4.25").
The driest month (with the least rainfall) is February (1.97").

[Resources]

Average rainfall days in September
Herculaneum, MO

Average rainfall days in September - Herculaneum, MO
  • Average rainfall days in September: 13 days

The month with the highest number of rainy days is July (17.8 days).
The month with the least rainy days is January (8.2 days).

[Resources]

Average snowfall in September
Herculaneum, MO

Average snowfall in September - Herculaneum, MO
  • Average snowfall in September: 0"

The month with the highest snowfall is January (2.36").
The months with the least snowfall are April, May, June, July, August, September and October (0").

[Resources]

Average snowfall days in September
Herculaneum, MO

Average snowfall days in September - Herculaneum, MO
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (6.8 days).
The months with the least snowfall days are April, May, June, July, August and September (0 days).

[Resources]

Average daylight in September /
Average sunshine in September
Herculaneum, MO

Average daylight in September / Average sunshine in September - Herculaneum, MO
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).

  • Average sunshine in September: 9h and 3min

The months with the most sunshine are June and July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 48min).

[Resources]

Average sunshine days in September
Herculaneum, MO

Average sunshine days in September - Herculaneum, MO
  • Average sunshine days in September: 14.6 days

The month with the most sunshine days is December (19.2 days).
The month with the least sunshine days is July (10.7 days).

[Resources]

Average UV index in September
Herculaneum, MO

Average UV index in September - Herculaneum, MO
  • Average UV index in September: 5

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

[Resources]

Average cloud cover in September
Herculaneum, MO

Average cloud cover in September - Herculaneum, MO
  • Average cloud cover in September: 29

The month with the most cloud cover is January (Cloud cover 49).
The months with the least cloud cover are June, July and August (Cloud cover 28).

[Resources]

Average visibility in September
Herculaneum, MO

Average visibility in September - Herculaneum, MO
  • 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).

[Resources]

Herculaneum, Missouri, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location