September weather forecast
Knox, IN

englishespañol中文
Share

Weather in September

The first month of the autumn, September, is also a moderately hot month in Knox, Indiana, with an average temperature fluctuating between 56.3°F (13.5°C) and 73.8°F (23.2°C).

Temperature

The unfolding of September shows an average high-temperature of a still moderately hot 73.8°F (23.2°C), indicating a slight variance from August's 78.8°F (26°C). During September, Knox records an average temperature of 56.3°F (13.5°C) at night.

Humidity

In September, the average relative humidity is 79%.

Rainfall

In Knox, in September, during 14.9 rainfall days, 2.17" (55mm) of precipitation is typically accumulated. In Knox, during the entire year, the rain falls for 175.4 days and collects up to 34.29" (871mm) of precipitation.

Snowfall

In Knox, Indiana, snow does not fall in June through September.

Daylight

In Knox, Indiana, the average length of the day in September is 12h and 28min.
On the first day of the month, sunrise is at 6:13 am and sunset at 7:18 pm. On the last day of September, sunrise is at 6:42 am and sunset at 6:29 pm CDT.

Sunshine

The average sunshine in September is 8.3h.

UV index

The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.
Note: The maximum daily UV index, 4 in September, converts into the following recommendations:
Make use of precautions - Shielding skin and eyes from injury is a requirement. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes.

Frequently asked questions

What are September temperatures in Knox?

The high-temperature in Knox during September is 73.8°F (23.2°C) and the low-temperature is 56.3°F (13.5°C).

What is the average humidity in September in Knox?

The average relative humidity in September in Knox is 79%.

How many days does it rain in September in Knox?

In September, in Knox, Indiana, the rain falls for 14.9 days. Throughout September, 2.17" (55mm) of precipitation is accumulated.

When it does not snow in Knox?

In Knox, Indiana, snow does not fall in June through September.

Does it snow in Knox in September?

In Knox, in September, it doesn't snow. In October, it regularly snows.

How many hours of daylight does Knox have in September?

In September, the average day length is 12h and 28min.

When is the sunrise / sunset in September in Knox?

In September, on the first day of the month, sunrise is at 6:13 am and sunset at 7:18 pm. On the last day of the month, in Knox, Indiana, sunrise is at 6:42 am and sunset at 6:29 pm CDT.

How long on average sun shines in September in Knox?

In September, the average sunshine duration in Knox, Indiana, is 8.3h.

How high is the UV index in September in Knox?

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a moderate vulnerability from unprotected exposure to 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
Knox, IN

Average temperature in September - Knox, IN
  • Average high temperature in September: 73.8°F

The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (29.8°F).

  • Average low temperature in September: 56.3°F

The month with the highest average low temperature is July (63.3°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).

Average pressure in September
Knox, IN

Average pressure in September - Knox, IN
  • Average pressure in September: 30.03"Hg

The months with the highest atmospheric pressure are January and November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).

Average wind speed in September
Knox, IN

Average wind speed in September - Knox, IN
  • Average wind speed in September: 7mph

The windiest month (with the highest average wind speed) is January (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.2mph).

Average humidity in September
Knox, IN

Average humidity in September - Knox, IN
  • Average humidity in September: 79%

The months with the highest relative humidity are January, February and July (84%).
The month with the lowest relative humidity is October (74%).

Average rainfall in September
Knox, IN

Average rainfall in September - Knox, IN
  • Average rainfall in September: 2.17"

The wettest month (with the highest rainfall) is May (4.45").
The driest month (with the least rainfall) is January (1.85").

Average rainfall days in September
Knox, IN

Average rainfall days in September - Knox, IN
  • Average rainfall days in September: 14.9 days

The month with the highest number of rainy days is May (20.7 days).
The month with the least rainy days is January (7.9 days).

Average snowfall in September
Knox, IN

Average snowfall in September - Knox, IN
  • Average snowfall in September: 0"

The month with the highest snowfall is February (5.04").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Knox, IN

Average snowfall days in September - Knox, IN
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (15.3 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Knox, IN

Average daylight in September / Average sunshine in September - Knox, IN
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).

  • Average sunshine in September: 8h and 2min

The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 24min).

Average sunshine days in September
Knox, IN

Average sunshine days in September - Knox, IN
  • Average sunshine days in September: 13 days

The month with the most sunshine days is November (14.6 days).
The month with the least sunshine days is June (7.8 days).

Average UV index in September
Knox, IN

Average UV index in September - Knox, IN
  • Average UV index in September: 4

The month with the highest UV index is June (UV index 6).
The month with the lowest UV index is December (UV index 1).

Average cloud cover in September
Knox, IN

Average cloud cover in September - Knox, IN
  • Average cloud cover in September: 35

The month with the most cloud cover is January (Cloud cover 65).
The month with the least cloud cover is August (Cloud cover 33).

Average visibility in September
Knox, IN

Average visibility in September - Knox, IN
  • Average visibility in September: 5mi

The months with the highest visibility are March, April, May, June, October, November and December (6mi).
The months with the lowest visibility are January, February, July, August and September (5mi).

Knox, Indiana, USA

Weather forecast for your location

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