September weather forecastSaint Ann, MO
September
Weather in September
September, the first month of the autumn in Saint Ann, is also a moderately hot month, with an average temperature varying between 79.7°F (26.5°C) and 60.1°F (15.6°C).Temperature
As September arrives, Saint Ann's weather displays a minor decrease in high-temperatures, transitioning from August's warm 85.5°F (29.7°C) to a still moderately hot 79.7°F (26.5°C). During September, Saint Ann's temperature averages to a moderate 60.1°F (15.6°C) at night.Humidity
The average relative humidity in September is 73%.Rainfall
In Saint Ann, in September, it is raining for 12.3 days, with typically 1.73" (44mm) of accumulated precipitation. Throughout the year, in Saint Ann, Missouri, there are 141.9 rainfall days, and 27.68" (703mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
The average length of the day in September in Saint Ann is 12h and 26min.On the first day of September, sunrise is at 6:31 am and sunset at 7:31 pm. On the last day of the month, sunrise is at 6:57 am and sunset at 6:45 pm CDT.
Sunshine
The average sunshine in September in Saint Ann is 9.6h.UV index
In Saint Ann, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: An average maximum UV index of 5 in September leads to these recommendations:
Put precautions into practice - Protective measures against sun-induced damage are advised. The Sun is at its harshest during midday; protect yourself by staying in shaded areas and minimizing exposure. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Saint Ann, MO
- Average high temperature in September: 79.7°F
The warmest month (with the highest average high temperature) is July (86.7°F).
The month with the lowest average high temperature is January (37.2°F).
- Average low temperature in September: 60.1°F
The month with the highest average low temperature is July (68.9°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure in September
Saint Ann, 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
Saint Ann, MO
- Average wind speed in September: 6.1mph
The windiest month (with the highest average wind speed) is January (9.3mph).
The calmest months (with the lowest average wind speed) are July and August (5.6mph).
Average humidity in September
Saint Ann, MO
- Average humidity in September: 73%
The month with the highest relative humidity is May (77%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Saint Ann, MO
- Average rainfall in September: 1.73"
The wettest month (with the highest rainfall) is May (3.31").
The driest month (with the least rainfall) is February (1.42").
Average rainfall days in September
Saint Ann, MO
- Average rainfall days in September: 12.3 days
The month with the highest number of rainy days is July (16.3 days).
The months with the least rainy days are February and December (7.3 days).
Average snowfall in September
Saint Ann, MO
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.05").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Saint Ann, 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 May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Saint Ann, 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 month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 36min).
Average sunshine days in September
Saint Ann, MO
- Average sunshine days in September: 15.3 days
The month with the most sunshine days is October (19.2 days).
The month with the least sunshine days is July (11.4 days).
Average UV index in September
Saint Ann, 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
Saint Ann, 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
Saint Ann, 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).





