September weather forecastMassena, IA
September
Weather in September
September, the first month of the autumn in Massena, is still a warm month, with an average temperature fluctuating between 55.9°F (13.3°C) and 74.8°F (23.8°C).Temperature
During the shift to September, a minor reduction in average high-temperature is observed, shifting from 80.8°F (27.1°C) in August to a still warm 74.8°F (23.8°C). Throughout September nights, Massena experiences a consistent temperature average of 55.9°F (13.3°C).Humidity
The average relative humidity in September is 76%.Rainfall
In Massena, in September, it is raining for 12.7 days, with typically 2.68" (68mm) of accumulated precipitation. Throughout the year, there are 138.2 rainfall days, and 28.23" (717mm) of precipitation is accumulated.Snowfall
In Massena, snow does not fall in June through September.Daylight
In September, the average length of the day is 12h and 28min.On the first day of September, sunrise is at 6:46 am and sunset at 7:51 pm. On the last day of the month, sunrise is at 7:15 am and sunset at 7:02 pm CDT.
Sunshine
In September, the average sunshine is 9.3h.UV index
The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for average individuals.Note: In September, a regular UV index of 4 translates into these guidelines:
Make use of precautions - Suggestions to resist sunburn are communicated. The Sun is at its harshest during midday; protect yourself by staying in shaded areas and minimizing exposure. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Massena, IA
- Average high temperature in September: 74.8°F
The warmest month (with the highest average high temperature) is July (82.4°F).
The month with the lowest average high temperature is January (28.4°F).
- Average low temperature in September: 55.9°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is January (14.9°F).
Average pressure in September
Massena, IA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in September
Massena, IA
- Average wind speed in September: 8.3mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity in September
Massena, IA
- Average humidity in September: 76%
The months with the highest relative humidity are January, February and June (82%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Massena, IA
- Average rainfall in September: 2.68"
The wettest month (with the highest rainfall) is June (4.49").
The driest month (with the least rainfall) is January (0.87").
Average rainfall days in September
Massena, IA
- Average rainfall days in September: 12.7 days
The month with the highest number of rainy days is June (18.5 days).
The month with the least rainy days is January (4 days).
Average snowfall in September
Massena, IA
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.41").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Massena, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Massena, IA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in September
Massena, IA
- Average sunshine days in September: 15.6 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is June (9.6 days).
Average UV index in September
Massena, IA
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Massena, IA
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 53).
The month with the least cloud cover is September (Cloud cover 29).
Average visibility in September
Massena, IA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).





