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 start of September involves a subtle temperature drop, shifting from a moderately hot 85.6°F (29.8°C) in August to a still warm 79.7°F (26.5°C). In the month of September, Arnold witnesses a consistent average low-temperature of 59.9°F (15.5°C).Humidity
In Arnold, the average relative humidity in September is 73%.Rainfall
In September, the rain falls for 12.6 days. Throughout September, 2.13" (54mm) of precipitation is accumulated. Throughout the year, there are 146.1 rainfall days, and 32.36" (822mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 25min.On the first day of September, sunrise is at 6:31 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:57 am and sunset at 6:45 pm CDT.
Sunshine
In September, the average sunshine is 9.4h.UV index
In September, the average daily maximum UV index in Arnold, Missouri, is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum daily UV index of 5 in September converts into the following recommendations:
Be vigilant - Preventing sunburn is recommended. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation.
Frequently asked questions
What are the temperatures in Arnold in September?
What is the average humidity in September in Arnold?
How much does it rain in Arnold in September?
When it does not snow in Arnold?
What is the average length of the day in September in Arnold?
What time are sunrise and sunset in September in Arnold?
How long on average sun shines in September in Arnold?
What is the UV index reading in September in Arnold?
Average temperature in September
Arnold, 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 (37.9°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (69.3°F).
The coldest month (with the lowest average low temperature) is January (25°F).
Average pressure in September
Arnold, 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
Arnold, MO
- Average wind speed in September: 5.9mph
The windiest month (with the highest average wind speed) is January (9.1mph).
The calmest months (with the lowest average wind speed) are July and August (5.5mph).
Average humidity in September
Arnold, 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 (71%).
Average rainfall in September
Arnold, MO
- Average rainfall in September: 2.13"
The wettest month (with the highest rainfall) is May (3.94").
The driest months (with the least rainfall) are February and November (1.77").
Average rainfall days in September
Arnold, MO
- Average rainfall days in September: 12.6 days
The month with the highest number of rainy days is July (16.9 days).
The months with the least rainy days are January and February (6.8 days).
Average snowfall in September
Arnold, 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
Arnold, MO
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (4.8 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
Arnold, 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 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
Arnold, MO
- Average sunshine days in September: 15.5 days
The month with the most sunshine days is January (20.9 days).
The month with the least sunshine days is June (11.6 days).
Average UV index in September
Arnold, 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
Arnold, MO
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
Arnold, 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).
Arnold, Missouri, USA
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