September weather forecastDiamond, MO
September
Weather in September
September, the first month of the autumn in Diamond, is also a moderately hot month, with an average temperature fluctuating between 61.2°F (16.2°C) and 80.6°F (27°C).Temperature
September is marked by a subtle drop in average high-temperatures, transitioning from a tropical 87.8°F (31°C) in August to a warm 80.6°F (27°C). Diamond throughout September, experiences an average nighttime temperature of 61.2°F (16.2°C).Heat index
The heat index value for September is appraised at 84.2°F (29°C). If one sustains activity during exposure, it could lead to a sense of fatigue, with a chance of heat cramps.Keep in mind the heat index values are meant for areas in shade and with light wind. The heat index values could be amplified by up to 15 Fahrenheit (8 Celsius) degrees in direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'real feel', binds temperature metrics with humidity values to give a sense of the actual warmth. One's perception of weather can be shaped by other factors, involving metabolic differences, pregnancy, and physical exertion. Consider that direct sun exposure can intensify the felt heat, adding potentially 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are highly important for children. Children often miss understanding the importance of rest and rehydration. Thirst usually appears late during dehydration - therefore, maintaining hydration, particularly during long physical activities, is essential.
Humidity
The average relative humidity in September is 73%.Rainfall
In September, the rain falls for 10.4 days. Throughout September, 1.18" (30mm) of precipitation is accumulated. In Diamond, during the entire year, the rain falls for 114.4 days and collects up to 13.9" (353mm) of precipitation.Snowfall
April, June through October are months without snowfall.Daylight
The average length of the day in September is 12h and 24min.On the first day of September, sunrise is at 6:48 am and sunset at 7:45 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 7:01 pm CDT.
Sunshine
In September, the average sunshine is 9.5h.UV index
In September, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for average individuals.Note: A typical high UV index of 5 in September suggests the following recommendations:
Undertake precautions - Obligation exists to protect against skin and eye damage. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Diamond, MO
- Average high temperature in September: 80.6°F
The warmest month (with the highest average high temperature) is July (89.4°F).
The month with the lowest average high temperature is January (43.2°F).
- Average low temperature in September: 61.2°F
The month with the highest average low temperature is July (69.4°F).
The coldest month (with the lowest average low temperature) is January (27.9°F).
Average pressure in September
Diamond, MO
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Diamond, MO
- Average wind speed in September: 7.5mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is July (6.8mph).
Average humidity in September
Diamond, MO
- Average humidity in September: 73%
The month with the highest relative humidity is May (78%).
The months with the lowest relative humidity are August and October (71%).
Average rainfall in September
Diamond, MO
- Average rainfall in September: 1.18"
The wettest month (with the highest rainfall) is May (2.24").
The driest months (with the least rainfall) are February and December (0.59").
Average rainfall days in September
Diamond, MO
- Average rainfall days in September: 10.4 days
The month with the highest number of rainy days is May (14.3 days).
The month with the least rainy days is December (5.1 days).
Average snowfall in September
Diamond, MO
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.47").
The months with the least snowfall are April, June, July, August, September and October (0").
Average snowfall days in September
Diamond, MO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Diamond, 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 42min).
- Average sunshine in September: 9h and 30min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is January (Average sunshine: 5h and 24min).
Average sunshine days in September
Diamond, MO
- Average sunshine days in September: 17.7 days
The month with the most sunshine days is December (23.7 days).
The month with the least sunshine days is May (14.1 days).
Average UV index in September
Diamond, MO
- Average UV index in September: 5
The month with the highest UV index is June (UV index 7).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in September
Diamond, MO
- Average cloud cover in September: 27
The months with the most cloud cover are February and March (Cloud cover 44).
The month with the least cloud cover is August (Cloud cover 24).
Average visibility in September
Diamond, 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).





