September weather forecastIrwin, IA
September
Weather in September
September, the first month of the autumn in Irwin, is still a warm month, with an average temperature varying between 55.9°F (13.3°C) and 75°F (23.9°C).Temperature
Irwin's weather in September, with an average high-temperature of a still warm 75°F (23.9°C), subtly shifts from August's 80.2°F (26.8°C). During the month of September, the temperature generally drops to a low average of 55.9°F (13.3°C).Humidity
In Irwin, Iowa, the average relative humidity in September is 75%.Rainfall
In September, the rain falls for 10.5 days. Throughout September, 1.65" (42mm) of precipitation is accumulated. In Irwin, during the entire year, the rain falls for 113.5 days and collects up to 15.71" (399mm) of precipitation.Snowfall
June through September are months without snowfall in Irwin.Daylight
The average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:47 am and sunset at 7:53 pm. On the last day of the month, sunrise is at 7:17 am and sunset at 7:03 pm CDT.
Sunshine
In Irwin, the average sunshine in September is 9.1h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for ordinary individuals.Note: An average maximum UV index of 4 in September leads to these recommendations:
Preventative actions are necessary - The mandate to avoid skin and eye damage is in place. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Irwin, IA
- Average high temperature in September: 75°F
The warmest month (with the highest average high temperature) is July (82.6°F).
The month with the lowest average high temperature is January (27.3°F).
- Average low temperature in September: 55.9°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (14.5°F).
Average pressure in September
Irwin, IA
- Average pressure in September: 30"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in September
Irwin, IA
- Average wind speed in September: 8.5mph
The windiest month (with the highest average wind speed) is April (10.9mph).
The calmest month (with the lowest average wind speed) is July (7.2mph).
Average humidity in September
Irwin, IA
- Average humidity in September: 75%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is October (68%).
Average rainfall in September
Irwin, IA
- Average rainfall in September: 1.65"
The wettest month (with the highest rainfall) is June (2.64").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days in September
Irwin, IA
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is June (16.1 days).
The month with the least rainy days is February (2.8 days).
Average snowfall in September
Irwin, IA
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.09").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Irwin, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Irwin, IA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 9h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).
Average sunshine days in September
Irwin, IA
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is December (21.6 days).
The month with the least sunshine days is June (11.4 days).
Average UV index in September
Irwin, IA
- Average UV index in September: 4
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, October, November and December (UV index 2).
Average cloud cover in September
Irwin, IA
- 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 July (Cloud cover 27).
Average visibility in September
Irwin, IA
- 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).
