Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The commencement of September indicates a gentle shift in the average high-temperature, receding from August's tropical 87.3°F (30.7°C) to a warm 80.2°F (26.8°C). Saint Clair experiences an average low-temperature of 59.2°F (15.1°C) in month of September.Humidity
The average relative humidity in September in Saint Clair is 74%.Rainfall
In September, the rain falls for 9.8 days. Throughout September, 1.46" (37mm) of precipitation is accumulated. In Saint Clair, during the entire year, the rain falls for 126.7 days and collects up to 20.63" (524mm) of precipitation.Snowfall
In Saint Clair, snow does not fall in April through October.Daylight
The average length of the day in September in Saint Clair is 12h and 25min.On the first day of September in Saint Clair, Missouri, sunrise is at 6:34 am and sunset at 7:33 pm. On the last day of the month, sunrise is at 6:59 am and sunset at 6:47 pm CDT.
Sunshine
In Saint Clair, the average sunshine in September is 9.4h.UV index
In Saint Clair, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for average individuals.Note: A daily high UV index of 5 in September leads to these guidelines:
Undertake protective steps - Recommendations to avoid sunburn are issued. The Sun's harshest UV rays are around midday; it's wise to seek shade and limit time outdoors. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Take heed! The reflection of snow can intensify the Sun's UV radiation nearly double.
Frequently asked questions
What is the average September temperature in Saint Clair?
What is the average humidity in September in Saint Clair?
How many days does it rain in September in Saint Clair?
When it does not snow in Saint Clair?
What is the average length of the day in September in Saint Clair?
What time are sunrise and sunset in September in Saint Clair?
How long on average sun shines in September in Saint Clair?
What is the UV index reading in September in Saint Clair?
Average temperature in September
Saint Clair, MO
- Average high temperature in September: 80.2°F
The warmest month (with the highest average high temperature) is July (88.9°F).
The month with the lowest average high temperature is January (39°F).
- Average low temperature in September: 59.2°F
The month with the highest average low temperature is July (68°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure in September
Saint Clair, 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 Clair, MO
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is January (8.5mph).
The calmest months (with the lowest average wind speed) are July and August (5.3mph).
Average humidity in September
Saint Clair, MO
- Average humidity in September: 74%
The month with the highest relative humidity is May (78%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Saint Clair, MO
- Average rainfall in September: 1.46"
The wettest months (with the highest rainfall) are April and May (2.48").
The driest months (with the least rainfall) are January and February (0.98").
Average rainfall days in September
Saint Clair, MO
- Average rainfall days in September: 9.8 days
The month with the highest number of rainy days is May (15.4 days).
The month with the least rainy days is January (5.9 days).
Average snowfall in September
Saint Clair, MO
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.57").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Saint Clair, MO
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is January (6.2 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Saint Clair, MO
- 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 30min).
- Average sunshine in September: 9h and 2min
The months with the most sunshine are June and July (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 42min).
Average sunshine days in September
Saint Clair, MO
- Average sunshine days in September: 18.1 days
The month with the most sunshine days is January (20.6 days).
The month with the least sunshine days is May (13.7 days).
Average UV index in September
Saint Clair, 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, November and December (UV index 2).
Average cloud cover in September
Saint Clair, MO
- Average cloud cover in September: 31
The months with the most cloud cover are January and February (Cloud cover 49).
The months with the least cloud cover are June and July (Cloud cover 29).
Average visibility in September
Saint Clair, MO
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, June, July, October, November and December (6mi).
The months with the lowest visibility are May, August and September (5mi).
Saint Clair, Missouri, USA
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