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
During September, the average high-temperature is a still warm 73.9°F (23.3°C), maintaining a close resemblance to that of the preceding month. Alta reports a consistent average low-temperature of 55.2°F (12.9°C) throughout September nights.Humidity
In Alta, the average relative humidity in September is 74%.Rainfall
In Alta, Iowa, in September, during 12.5 rainfall days, 2.32" (59mm) of precipitation is typically accumulated. Throughout the year, in Alta, there are 135.1 rainfall days, and 26.73" (679mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 29min.On the first day of September, sunrise is at 6:46 am and sunset at 7:55 pm. On the last day of the month, sunrise is at 7:18 am and sunset at 7:03 pm CDT.
Sunshine
In September, the average sunshine is 9.1h.UV index
In Alta, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Make use of precautions - Shielding skin and eyes from injury is a requirement. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in Alta in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
Does it snow in September?
How many hours of daylight does Alta have in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Alta, IA
- Average high temperature in September: 73.9°F
The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is January (24.6°F).
- Average low temperature in September: 55.2°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (12.6°F).
Average pressure in September
Alta, IA
- Average pressure in September: 30"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in September
Alta, IA
- Average wind speed in September: 8.8mph
The windiest months (with the highest average wind speed) are January and April (11.2mph).
The calmest month (with the lowest average wind speed) is July (7.5mph).
Average humidity in September
Alta, IA
- Average humidity in September: 74%
The month with the highest relative humidity is January (85%).
The months with the lowest relative humidity are April and October (68%).
Average rainfall in September
Alta, IA
- Average rainfall in September: 2.32"
The wettest month (with the highest rainfall) is June (4.02").
The driest month (with the least rainfall) is January (0.91").
Average rainfall days in September
Alta, IA
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is June (19 days).
The month with the least rainy days is February (3.7 days).
Average snowfall in September
Alta, IA
- Average snowfall in September: 0"
The month with the highest snowfall is February (5.79").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Alta, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (12.6 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, 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: 9h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in September
Alta, IA
- Average sunshine days in September: 15.1 days
The month with the most sunshine days is November (18.8 days).
The month with the least sunshine days is June (8.1 days).
Average UV index in September
Alta, IA
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and February (UV index 1).
Average cloud cover in September
Alta, IA
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in September
Alta, IA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Alta, Iowa, USA
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