September weather forecastFrontenac, MO
September
Weather in September
September, the first month of the autumn in Frontenac, is still a warm month, with an average temperature ranging between max 79.7°F (26.5°C) and min 60.1°F (15.6°C).Temperature
Frontenac's transition into September involves a gentle shift in temperature, receding from a moderately hot 85.5°F (29.7°C) in August to a still warm 79.7°F (26.5°C). Throughout September, an average low-temperature of 60.1°F (15.6°C) is expected.Humidity
In Frontenac, the average relative humidity in September is 73%.Rainfall
In Frontenac, during September, the rain falls for 12 days and regularly aggregates up to 1.97" (50mm) of precipitation. Throughout the year, there are 144.8 rainfall days, and 30.59" (777mm) of precipitation is accumulated.Snowfall
In Frontenac, snow does not fall in April through October.Daylight
In September, the average length of the day in Frontenac is 12h and 25min.On the first day of the month, sunrise is at 6:31 am and sunset at 7:31 pm. On the last day of September, sunrise is at 6:57 am and sunset at 6:45 pm CDT.
Sunshine
In September, the average sunshine is 9.6h.UV index
In Frontenac, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum daily UV index of 5 in September converts into the following recommendations:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes. Be informed! The Sun's UV radiation can be nearly doubled due to the reflection from snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Frontenac, MO
- Average high temperature in September: 79.7°F
The warmest month (with the highest average high temperature) is July (86.9°F).
The month with the lowest average high temperature is January (37.8°F).
- Average low temperature in September: 60.1°F
The month with the highest average low temperature is July (69.1°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure in September
Frontenac, 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).
Average wind speed in September
Frontenac, MO
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is January (9.2mph).
The calmest months (with the lowest average wind speed) are July and August (5.5mph).
Average humidity in September
Frontenac, MO
- Average humidity in September: 73%
The month with the highest relative humidity is May (78%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Frontenac, MO
- Average rainfall in September: 1.97"
The wettest month (with the highest rainfall) is May (3.58").
The driest month (with the least rainfall) is February (1.69").
Average rainfall days in September
Frontenac, MO
- Average rainfall days in September: 12 days
The month with the highest number of rainy days is May (16.9 days).
The month with the least rainy days is January (6.5 days).
Average snowfall in September
Frontenac, MO
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.6").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Frontenac, MO
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (5.2 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Frontenac, MO
- Average daylight in September: 12h and 24min
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 30min).
- Average sunshine in September: 9h and 36min
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 36min).
Average sunshine days in September
Frontenac, MO
- Average sunshine days in September: 15.2 days
The month with the most sunshine days is January (21 days).
The month with the least sunshine days is June (11.2 days).
Average UV index in September
Frontenac, 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 and December (UV index 2).
Average cloud cover in September
Frontenac, MO
- Average cloud cover in September: 28
The month with the most cloud cover is January (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Frontenac, 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).





