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 beginning of September brings a slight decrease in the average high-temperature, transitioning from 84°F (28.9°C) in August to a still warm 78.6°F (25.9°C). During the nights in September, the temperature averages to a mild 59.5°F (15.3°C).Humidity
In West Alton, the average relative humidity in September is 74%.Rainfall
In West Alton, in September, it is raining for 10.5 days, with typically 1.3" (33mm) of accumulated precipitation. Throughout the year, there are 128.3 rainfall days, and 18.9" (480mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall in West Alton.Daylight
In West Alton, the average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 6:30 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:56 am and sunset at 6:44 pm CDT.
Sunshine
In West Alton, the average sunshine in September is 9.3h.UV index
In West Alton, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: The maximum UV index of 5 during September leads to these instructions:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
How many hours of daylight does West Alton have in September?
What time are sunrise and sunset in September?
How many hours of sunshine does West Alton have in September?
How high is the UV index in September?
Average temperature in September
West Alton, MO
- Average high temperature in September: 78.6°F
The warmest month (with the highest average high temperature) is July (85.3°F).
The month with the lowest average high temperature is January (36.1°F).
- Average low temperature in September: 59.5°F
The month with the highest average low temperature is July (67.6°F).
The coldest month (with the lowest average low temperature) is January (23.2°F).
Average pressure in September
West Alton, 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
West Alton, MO
- Average wind speed in September: 6.3mph
The windiest month (with the highest average wind speed) is January (9.6mph).
The calmest month (with the lowest average wind speed) is July (5.7mph).
Average humidity in September
West Alton, MO
- Average humidity in September: 74%
The month with the highest relative humidity is July (80%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
West Alton, MO
- Average rainfall in September: 1.3"
The wettest month (with the highest rainfall) is May (2.44").
The driest month (with the least rainfall) is February (0.83").
Average rainfall days in September
West Alton, MO
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is July (15.4 days).
The month with the least rainy days is January (5.7 days).
Average snowfall in September
West Alton, MO
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.14").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
West Alton, MO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.4 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
West Alton, 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 months with the least sunshine are January and February (Average sunshine: 4h and 30min).
Average sunshine days in September
West Alton, MO
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is December (21 days).
The month with the least sunshine days is June (12.6 days).
Average UV index in September
West Alton, 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
West Alton, MO
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
West Alton, 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).
West Alton, Missouri, USA
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