September weather forecastDewar, IA
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Dewar, Iowa, with an average temperature varying between 73.2°F (22.9°C) and 54.5°F (12.5°C).Temperature
Dewar's progression into September involves a gentle drop in the average high-temperature, from a moderately hot 78.6°F (25.9°C) in August to a pleasant 73.2°F (22.9°C). An average low-temperature of 54.5°F (12.5°C) is recorded during the nights in September.Humidity
The average relative humidity in September is 78%.Rainfall
In Dewar, in September, it is raining for 11.2 days, with typically 2.48" (63mm) of accumulated precipitation. Throughout the year, there are 133.6 rainfall days, and 28.27" (718mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:34 am and sunset at 7:42 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 6:51 pm CDT.
Sunshine
The average sunshine in September is 9.1h.UV index
In Dewar, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: The daily high UV index of 4 during September translates into the following recommendations:
Take precautions - Protection against skin and eye damage is obliged. Exposing oneself to the midday Sun can be harmful due to the strong UV radiation; limit your time outside. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Dewar, IA
- Average high temperature in September: 73.2°F
The warmest month (with the highest average high temperature) is July (80.1°F).
The month with the lowest average high temperature is January (24.3°F).
- Average low temperature in September: 54.5°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (12°F).
Average pressure in September
Dewar, 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 (29.89"Hg).
Average wind speed in September
Dewar, IA
- Average wind speed in September: 8.2mph
The windiest month (with the highest average wind speed) is April (10.8mph).
The calmest month (with the lowest average wind speed) is August (7mph).
Average humidity in September
Dewar, IA
- Average humidity in September: 78%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Dewar, IA
- Average rainfall in September: 2.48"
The wettest month (with the highest rainfall) is June (4.29").
The driest months (with the least rainfall) are January and February (1.02").
Average rainfall days in September
Dewar, IA
- Average rainfall days in September: 11.2 days
The month with the highest number of rainy days is June (18.1 days).
The month with the least rainy days is February (4 days).
Average snowfall in September
Dewar, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.21").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Dewar, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Dewar, IA
- Average daylight in September: 12h and 30min
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: 9h and 6min
The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Dewar, IA
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is October (17.8 days).
The month with the least sunshine days is June (10 days).
Average UV index in September
Dewar, IA
- Average UV index in September: 4
The month with the highest UV index is June (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Dewar, IA
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in September
Dewar, IA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, July and August (5mi).
