September weather forecastThayer, IA
September
Weather in September
September, the first month of the autumn in Thayer, is still a warm month, with an average temperature fluctuating between 56.1°F (13.4°C) and 75.4°F (24.1°C).Temperature
September's arrival signals a moderate reduction in the average high-temperature, easing from a moderately hot 81.7°F (27.6°C) in August to a still warm 75.4°F (24.1°C). The mean low-temperature during September nights is a mild 56.1°F (13.4°C).Humidity
In September, the average relative humidity is 77%.Rainfall
In September, the rain falls for 10.7 days. Throughout September, 1.81" (46mm) of precipitation is accumulated. In Thayer, during the entire year, the rain falls for 122.6 days and collects up to 20.43" (519mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September in Thayer is 12h and 27min.On the first day of the month, sunrise is at 6:43 am and sunset at 7:48 pm. On the last day of September, sunrise is at 7:12 am and sunset at 6:59 pm CDT.
Sunshine
In Thayer, the average sunshine in September is 9.3h.UV index
The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the average person.Note: A maximum high daily UV index of 4 during September translates into the following directions:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Thayer, IA
- Average high temperature in September: 75.4°F
The warmest month (with the highest average high temperature) is July (83.3°F).
The month with the lowest average high temperature is January (29.1°F).
- Average low temperature in September: 56.1°F
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (15.8°F).
Average pressure in September
Thayer, 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 (29.89"Hg).
Average wind speed in September
Thayer, IA
- Average wind speed in September: 8.1mph
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
Thayer, IA
- Average humidity in September: 77%
The month with the highest relative humidity is June (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Thayer, IA
- Average rainfall in September: 1.81"
The wettest month (with the highest rainfall) is June (3.74").
The driest month (with the least rainfall) is December (0.63").
Average rainfall days in September
Thayer, IA
- Average rainfall days in September: 10.7 days
The months with the highest number of rainy days are May and June (16.4 days).
The months with the least rainy days are January and February (3.7 days).
Average snowfall in September
Thayer, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.66").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Thayer, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Thayer, 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 18min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).
Average sunshine days in September
Thayer, IA
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is December (21 days).
The months with the least sunshine days are May and June (11.3 days).
Average UV index in September
Thayer, 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
Thayer, 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
Thayer, IA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, September, October, November and December (6mi).
The month with the lowest visibility is August (5mi).





