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 arrival of September corresponds with a light shift in temperature, down from a moderately hot 77.5°F (25.3°C) in August to a pleasant 72.1°F (22.3°C). Throughout the nights in September, Colwell experiences an average low-temperature of 53.4°F (11.9°C).Humidity
In September, the average relative humidity is 79%.Rainfall
In Colwell, in September, it is raining for 11.2 days, with typically 2.09" (53mm) of accumulated precipitation. Throughout the year, there are 136.1 rainfall days, and 27.32" (694mm) of precipitation is accumulated.Snowfall
In Colwell, snow does not fall in June through September.Daylight
In September, the average length of the day is 12h and 29min.On the first day of September, sunrise is at 6:35 am and sunset at 7:44 pm. On the last day of the month, sunrise is at 7:07 am and sunset at 6:52 pm CDT.
Sunshine
In September, the average sunshine is 8.9h.UV index
In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: In September, the maximum UV index of 4 translates into these guidelines:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures in Colwell?
What is the average humidity in September?
How much does it rain in Colwell in September?
When it does not snow?
Does it snow in September?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Colwell, IA
- Average high temperature in September: 72.1°F
The warmest month (with the highest average high temperature) is July (79.2°F).
The month with the lowest average high temperature is January (22.6°F).
- Average low temperature in September: 53.4°F
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (10.6°F).
Average pressure in September
Colwell, IA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in September
Colwell, IA
- Average wind speed in September: 8.3mph
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 (7.1mph).
Average humidity in September
Colwell, IA
- Average humidity in September: 79%
The month with the highest relative humidity is January (88%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Colwell, IA
- Average rainfall in September: 2.09"
The wettest month (with the highest rainfall) is June (4.17").
The driest month (with the least rainfall) is January (1.14").
Average rainfall days in September
Colwell, IA
- Average rainfall days in September: 11.2 days
The month with the highest number of rainy days is May (19.2 days).
The month with the least rainy days is February (4.3 days).
Average snowfall in September
Colwell, IA
- Average snowfall in September: 0"
The month with the highest snowfall is February (6.5").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Colwell, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (14.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Colwell, IA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 5min
The months with the most sunshine are July and August (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in September
Colwell, IA
- Average sunshine days in September: 16.8 days
The month with the most sunshine days is October (17.5 days).
The month with the least sunshine days is June (9.3 days).
Average UV index in September
Colwell, IA
- Average UV index in September: 4
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January, February and December (UV index 1).
Average cloud cover in September
Colwell, IA
- Average cloud cover in September: 33
The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in September
Colwell, IA
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, September, October and November (6mi).
The months with the lowest visibility are January, February, July, August and December (5mi).
Colwell, Iowa, USA
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