Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The shift from August to September coincides with a small decrease in the average high-temperature, down to a still warm 75.2°F (24°C) from 80.6°F (27°C). September's nights observe an average temperature of 55.8°F (13.2°C).Humidity
In Windham, the average relative humidity in September is 76%.Rainfall
In Windham, Iowa, in September, during 12 rainfall days, 2.44" (62mm) of precipitation is typically accumulated. Throughout the year, there are 140.4 rainfall days, and 29.57" (751mm) of precipitation is accumulated.Snowfall
In Windham, snow does not fall in May through September.Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:33 am and sunset at 7:39 pm. On the last day of September, sunrise is at 7:03 am and sunset at 6:49 pm CDT.
Sunshine
The average sunshine in September is 9.3h.UV index
In Windham, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum daily UV index of 4 in September interprets into the following recommendations:
Put precautions into practice - Ensuring skin and eye safety is a necessity. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
Does it snow in Windham in September?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Windham, IA
- Average high temperature in September: 75.2°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (27.3°F).
- Average low temperature in September: 55.8°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (15.3°F).
Average pressure in September
Windham, IA
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Windham, IA
- Average wind speed in September: 8mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (6.9mph).
Average humidity in September
Windham, IA
- Average humidity in September: 76%
The months with the highest relative humidity are January and July (83%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Windham, IA
- Average rainfall in September: 2.44"
The wettest month (with the highest rainfall) is May (4.69").
The driest months (with the least rainfall) are January and February (1.34").
Average rainfall days in September
Windham, IA
- Average rainfall days in September: 12 days
The month with the highest number of rainy days is May (18.4 days).
The month with the least rainy days is February (5 days).
Average snowfall in September
Windham, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (5.28").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Windham, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.9 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
Windham, IA
- Average daylight in September: 12h and 3min
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 12min).
- Average sunshine in September: 9h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days in September
Windham, IA
- Average sunshine days in September: 17.1 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (10 days).
Average UV index in September
Windham, IA
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Windham, IA
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 56).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in September
Windham, IA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).
Windham, Iowa, USA
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