September weather forecastAlta Vista, IA
September
Weather in September
September, the first month of the autumn in Alta Vista, is still a pleasant month, with an average temperature fluctuating between 52.9°F (11.6°C) and 71.8°F (22.1°C).Temperature
September witnesses a gentle descent in average high-temperature, descending from August's warm 77.4°F (25.2°C) to an agreeable 71.8°F (22.1°C). During September, the temperature in Alta Vista tends to dip to an average of 52.9°F (11.6°C) at night.Humidity
The average relative humidity in September in Alta Vista is 79%.Rainfall
In Alta Vista, during September, the rain falls for 8.3 days and regularly aggregates up to 0.87" (22mm) of precipitation. In Alta Vista, during the entire year, the rain falls for 98 days and collects up to 9.8" (249mm) of precipitation.Snowfall
In Alta Vista, Iowa, snow does not fall in June through September.Daylight
The average length of the day in September is 12h and 29min.On the first day of September, sunrise is at 6:34 am and sunset at 7:44 pm. On the last day of the month, sunrise is at 7:06 am and sunset at 6:52 pm CDT.
Sunshine
The average sunshine in September is 9h.UV index
The average daily maximum UV index in September in Alta Vista is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for the average person.Note: In September, the maximum UV index of 4 suggests this advice:
Guard yourself - An obligation to protect skin and eyes from harm exists. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Alta Vista, IA
- Average high temperature in September: 71.8°F
The warmest month (with the highest average high temperature) is July (79°F).
The month with the lowest average high temperature is January (22.5°F).
- Average low temperature in September: 52.9°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
Alta Vista, 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
Alta Vista, 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 (7.2mph).
Average humidity in September
Alta Vista, IA
- Average humidity in September: 79%
The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Alta Vista, IA
- Average rainfall in September: 0.87"
The wettest month (with the highest rainfall) is June (1.5").
The driest month (with the least rainfall) is January (0.31").
Average rainfall days in September
Alta Vista, IA
- Average rainfall days in September: 8.3 days
The month with the highest number of rainy days is June (14.5 days).
The month with the least rainy days is February (2 days).
Average snowfall in September
Alta Vista, IA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.85").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Alta Vista, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Alta Vista, 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 0min).
- Average sunshine in September: 9h and 0min
The month with the most sunshine is July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in September
Alta Vista, IA
- Average sunshine days in September: 19.4 days
The month with the most sunshine days is November (22 days).
The month with the least sunshine days is June (13.3 days).
Average UV index in September
Alta Vista, 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, November and December (UV index 1).
Average cloud cover in September
Alta Vista, 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
Alta Vista, IA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January and July (5mi).
