September weather forecastVandalia, MO
September
Weather in September
September, the first month of the autumn in Vandalia, is still a warm month, with an average temperature ranging between min 58.8°F (14.9°C) and max 78.3°F (25.7°C).Temperature
September is characterized by a slight reduction in average high-temperature, easing from a moderately hot 84.2°F (29°C) in August to a still warm 78.3°F (25.7°C). Vandalia experiences a nighttime temperature average of 58.8°F (14.9°C) during September.Humidity
In September, the average relative humidity is 74%.Rainfall
In Vandalia, during September, the rain falls for 11.9 days and regularly aggregates up to 2.28" (58mm) of precipitation. In Vandalia, during the entire year, the rain falls for 142.4 days and collects up to 28.98" (736mm) of precipitation.Snowfall
In Vandalia, snow does not fall in May through September.Daylight
In Vandalia, the average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:35 am and sunset at 7:36 pm. On the last day of September, sunrise is at 7:01 am and sunset at 6:49 pm CDT.
Sunshine
In Vandalia, the average sunshine in September is 9.3h.UV index
The average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for average individuals.Note: The UV index of 5 in September translates into these instructions:
Be vigilant - A duty to shield skin and eyes from injury exists. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Experience reduced UV exposure by about half when donning a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Vandalia, MO
- Average high temperature in September: 78.3°F
The warmest month (with the highest average high temperature) is July (85.5°F).
The month with the lowest average high temperature is January (35.2°F).
- Average low temperature in September: 58.8°F
The month with the highest average low temperature is July (67.5°F).
The coldest month (with the lowest average low temperature) is January (21.9°F).
Average pressure in September
Vandalia, 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 (29.91"Hg).
Average wind speed in September
Vandalia, MO
- Average wind speed in September: 6.8mph
The windiest months (with the highest average wind speed) are January and February (9.8mph).
The calmest months (with the lowest average wind speed) are July and August (6.2mph).
Average humidity in September
Vandalia, MO
- Average humidity in September: 74%
The months with the highest relative humidity are May and July (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Vandalia, MO
- Average rainfall in September: 2.28"
The wettest month (with the highest rainfall) is May (3.62").
The driest month (with the least rainfall) is January (1.46").
Average rainfall days in September
Vandalia, MO
- Average rainfall days in September: 11.9 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is January (5.9 days).
Average snowfall in September
Vandalia, MO
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.7").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Vandalia, MO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (7.5 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
Vandalia, MO
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).
Average sunshine days in September
Vandalia, MO
- Average sunshine days in September: 16.7 days
The month with the most sunshine days is December (20 days).
The month with the least sunshine days is May (11.5 days).
Average UV index in September
Vandalia, MO
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Vandalia, MO
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 51).
The months with the least cloud cover are June, July and August (Cloud cover 29).
Average visibility in September
Vandalia, 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).
