September weather forecastMerwin, MO
September
Weather in September
The first month of the autumn, September, is still a warm month in Merwin, Missouri, with an average temperature varying between 59.9°F (15.5°C) and 78.1°F (25.6°C).Temperature
September brings a slight decrease in the average high-temperature, shifting from 84.9°F (29.4°C) in August to a still moderately hot 78.1°F (25.6°C). Throughout September, Merwin's nights cool down to an average of 59.9°F (15.5°C).Humidity
In September, the average relative humidity is 77%.Rainfall
In Merwin, in September, during 10.7 rainfall days, 1.34" (34mm) of precipitation is typically accumulated. In Merwin, during the entire year, the rain falls for 114.1 days and collects up to 13.9" (353mm) of precipitation.Snowfall
April, June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 25min.On the first day of September, sunrise is at 6:48 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 7:02 pm CDT.
Sunshine
In September, the average sunshine is 9.2h.UV index
In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: The daily maximum UV index of 5 in September interprets into the following advice:
Prioritize safety - Suggestions to prevent sun damage are offered. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Merwin, MO
- Average high temperature in September: 78.1°F
The warmest month (with the highest average high temperature) is July (86.5°F).
The month with the lowest average high temperature is January (38.8°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (68.9°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure in September
Merwin, MO
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Merwin, MO
- Average wind speed in September: 7.1mph
The windiest month (with the highest average wind speed) is March (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (6.6mph).
Average humidity in September
Merwin, MO
- Average humidity in September: 77%
The month with the highest relative humidity is May (81%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Merwin, MO
- Average rainfall in September: 1.34"
The wettest month (with the highest rainfall) is May (2.6").
The driest month (with the least rainfall) is January (0.35").
Average rainfall days in September
Merwin, MO
- Average rainfall days in September: 10.7 days
The month with the highest number of rainy days is May (15.2 days).
The month with the least rainy days is January (3.5 days).
Average snowfall in September
Merwin, MO
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.71").
The months with the least snowfall are April, June, July, August and September (0").
Average snowfall days in September
Merwin, MO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Merwin, MO
- Average daylight in September: 12h and 24min
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 12min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 5h and 18min).
Average sunshine days in September
Merwin, MO
- Average sunshine days in September: 17 days
The month with the most sunshine days is January (25.2 days).
The month with the least sunshine days is May (12.8 days).
Average UV index in September
Merwin, 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
Merwin, MO
- Average cloud cover in September: 29
The month with the most cloud cover is March (Cloud cover 46).
The months with the least cloud cover are July and August (Cloud cover 26).
Average visibility in September
Merwin, 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).





