September weather forecastIrondale, MO
September
Weather in September
September, the first month of the autumn in Irondale, is also a moderately hot month, with an average temperature varying between 79.9°F (26.6°C) and 58.8°F (14.9°C).Temperature
September's arrival comes with a mild decrease in the average high-temperature, moving subtly from a hot 86.7°F (30.4°C) in August to a moderately hot 79.9°F (26.6°C). Irondale observes an average low-temperature of 58.8°F (14.9°C) during September.Humidity
In Irondale, the average relative humidity in September is 75%.Rainfall
September is the month with the least rainfall. Rain falls for 13.5 days and accumulates 1.77" (45mm) of precipitation.Snowfall
In Irondale, snow does not fall in April through October.Daylight
In September, the average length of the day in Irondale is 12h and 25min.On the first day of the month, sunrise is at 6:33 am and sunset at 7:31 pm. On the last day of September, in Irondale, sunrise is at 6:58 am and sunset at 6:46 pm CDT.
Sunshine
The average sunshine in September in Irondale, Missouri, is 9.4h.UV index
The average daily maximum UV index in September in Irondale is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: During September, 5 as the daily maximum UV index converts into the following advice:
Stay alert. Light-skinned people could suffer burns in less than 30 minutes. Around midday, solar radiation is most harmful; hence, exposure should be limited. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Irondale, MO
- Average high temperature in September: 79.9°F
The warmest month (with the highest average high temperature) is July (88°F).
The month with the lowest average high temperature is January (39.6°F).
- Average low temperature in September: 58.8°F
The month with the highest average low temperature is July (67.3°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).
Average pressure in September
Irondale, 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 (29.93"Hg).
Average wind speed in September
Irondale, MO
- Average wind speed in September: 5.3mph
The windiest month (with the highest average wind speed) is January (8.6mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in September
Irondale, MO
- Average humidity in September: 75%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Irondale, MO
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is May (3.78").
The driest month (with the least rainfall) is September (1.77").
Average rainfall days in September
Irondale, MO
- Average rainfall days in September: 13.5 days
The month with the highest number of rainy days is July (17.2 days).
The month with the least rainy days is December (7.9 days).
Average snowfall in September
Irondale, MO
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.72").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Irondale, MO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (6.5 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
Irondale, MO
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 9h and 24min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The months with the least sunshine are January and February (Average sunshine: 4h and 48min).
Average sunshine days in September
Irondale, MO
- Average sunshine days in September: 14.5 days
The months with the most sunshine days are November and December (18.9 days).
The month with the least sunshine days is July (10.9 days).
Average UV index in September
Irondale, 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
Irondale, MO
- Average cloud cover in September: 31
The month with the most cloud cover is February (Cloud cover 49).
The month with the least cloud cover is June (Cloud cover 29).
Average visibility in September
Irondale, MO
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, June, October, November and December (6mi).
The months with the lowest visibility are May, July, August and September (5mi).





