September weather forecast
Mount Vernon, IN

Share

Weather in September

The first month of the autumn, September, is still a warm month in Mount Vernon, Indiana, with an average temperature varying between 61.2°F (16.2°C) and 79.7°F (26.5°C).

Temperature

As August transitions into September, Mount Vernon records an average high-temperature of a still moderately hot 79.7°F (26.5°C), showing a gentle shift from the preceding month. Mount Vernon experiences an average low-temperature reading of 61.2°F (16.2°C) throughout September.

Humidity

In Mount Vernon, the average relative humidity in September is 73%.

Rainfall

The month with the least rainfall is September, when the rain falls for 12.5 days and typically collects 1.85" (47mm) of precipitation.

Snowfall

May through October are months without snowfall.

Daylight

The average length of the day in September in Mount Vernon is 12h and 25min.
On the first day of September in Mount Vernon, sunrise is at 6:22 am and sunset at 7:20 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:35 pm CDT.

Sunshine

In Mount Vernon, Indiana, the average sunshine in September is 9h.

UV index

In September, the average daily maximum UV index in Mount Vernon, Indiana, is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for average individuals.
Note: In September, the maximum UV index of 5 suggests these recommendations:
Exercise prevention - Protecting skin and eyes from harm is required. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the average September temperature in Mount Vernon?

Mount Vernon in September has an average high-temperature of 79.7°F (26.5°C) and an average low-temperature of 61.2°F (16.2°C). In August, the average heat index (a.k.a. 'felt air temperature', 'real feel'), which combines relative humidity and air temperature, is evaluated at 95°F (35°C).

What is the average humidity in September in Mount Vernon?

The average relative humidity in September in Mount Vernon, Indiana, is 73%.

What is the driest month in Mount Vernon?

The month with the least rainfall is September, when the rain falls for 12.5 days and typically collects 1.85" (47mm) of precipitation.

How many days does it rain in September in Mount Vernon?

In Mount Vernon, during September, the rain falls for 12.5 days and regularly aggregates up to 1.85" (47mm) of precipitation.

When it does not snow in Mount Vernon?

In Mount Vernon, Indiana, snow does not fall in May through October.

What is the average length of the day in September in Mount Vernon?

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

What time are sunrise and sunset in September in Mount Vernon?

On the first day of September, sunrise is at 6:22 am and sunset at 7:20 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:35 pm CDT.

How many hours of sunshine does Mount Vernon have in September?

In September, the average sunshine duration is 9h.

How high is the UV index in September in Mount Vernon?

In Mount Vernon, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a medium hazard to health 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
Mount Vernon, IN

Average temperature in September - Mount Vernon, IN
  • Average high temperature in September: 79.7°F

The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (39.4°F).

  • Average low temperature in September: 61.2°F

The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (26.4°F).

Average pressure in September
Mount Vernon, IN

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

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).

Average wind speed in September
Mount Vernon, IN

Average wind speed in September - Mount Vernon, IN
  • Average wind speed in September: 6.7mph

The windiest month (with the highest average wind speed) is February (10.1mph).
The calmest month (with the lowest average wind speed) is July (5.9mph).

Average humidity in September
Mount Vernon, IN

Average humidity in September - Mount Vernon, IN
  • Average humidity in September: 73%

The months with the highest relative humidity are May and July (79%).
The month with the lowest relative humidity is October (69%).

Average rainfall in September
Mount Vernon, IN

Average rainfall in September - Mount Vernon, IN
  • Average rainfall in September: 1.85"

The wettest month (with the highest rainfall) is April (5.28").
The driest month (with the least rainfall) is September (1.85").

Average rainfall days in September
Mount Vernon, IN

Average rainfall days in September - Mount Vernon, IN
  • Average rainfall days in September: 12.5 days

The month with the highest number of rainy days is May (19.5 days).
The month with the least rainy days is January (10.3 days).

Average snowfall in September
Mount Vernon, IN

Average snowfall in September - Mount Vernon, IN
  • Average snowfall in September: 0"

The month with the highest snowfall is January (1.85").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in September
Mount Vernon, IN

Average snowfall days in September - Mount Vernon, IN
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (6.5 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Mount Vernon, IN

Average daylight in September / Average sunshine in September - Mount Vernon, IN
  • 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 0min

The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).

Average sunshine days in September
Mount Vernon, IN

Average sunshine days in September - Mount Vernon, IN
  • Average sunshine days in September: 14.7 days

The month with the most sunshine days is October (18.5 days).
The month with the least sunshine days is May (9.3 days).

Average UV index in September
Mount Vernon, IN

Average UV index in September - Mount Vernon, IN
  • 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 and December (UV index 2).

Average cloud cover in September
Mount Vernon, IN

Average cloud cover in September - Mount Vernon, IN
  • Average cloud cover in September: 29

The month with the most cloud cover is January (Cloud cover 53).
The month with the least cloud cover is June (Cloud cover 28).

Average visibility in September
Mount Vernon, IN

Average visibility in September - Mount Vernon, IN
  • 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).

Mount Vernon, Indiana, USA

Weather forecast for your location

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