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 average high-temperature shows a slight dip in September, from August's 81.7°F (27.6°C) to a still moderately hot 75.6°F (24.2°C). Throughout September, Norwalk's nights cool down to an average of 55.9°F (13.3°C).Humidity
In September, the average relative humidity is 76%.Rainfall
In Norwalk, in September, during 10.5 rainfall days, 1.73" (44mm) of precipitation is typically accumulated. In Norwalk, during the entire year, the rain falls for 114.4 days and collects up to 16.38" (416mm) of precipitation.Snowfall
June through September are months without snowfall in Norwalk, Iowa.Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:41 am and sunset at 7:47 pm. On the last day of September, in Norwalk, sunrise is at 7:11 am and sunset at 6:57 pm CDT.
Sunshine
In September, the average sunshine in Norwalk is 9.3h.UV index
In September, the average daily maximum UV index in Norwalk is 4. A UV Index reading of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for the ordinary person.Note: In September, the maximum UV index of 4 translates into these guidelines:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. Midday is when the Sun's radiation is strongest; avoid prolonged exposure during this time. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure.
Frequently asked questions
What is the average September temperature in Norwalk?
What is the average humidity in September in Norwalk?
How much does it rain in Norwalk in September?
When it does not snow in Norwalk?
Does it snow in Norwalk in September?
What is the average length of the day in September in Norwalk?
When is the sunrise / sunset in September in Norwalk?
How long on average sun shines in September in Norwalk?
What is the UV index reading in September in Norwalk?
Average temperature in September
Norwalk, IA
- Average high temperature in September: 75.6°F
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (28.2°F).
- Average low temperature in September: 55.9°F
The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (15.1°F).
Average pressure in September
Norwalk, 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 (29.88"Hg).
Average wind speed in September
Norwalk, IA
- Average wind speed in September: 8mph
The windiest months (with the highest average wind speed) are January, February, March and April (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (7mph).
Average humidity in September
Norwalk, IA
- Average humidity in September: 76%
The months with the highest relative humidity are January and June (82%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Norwalk, IA
- Average rainfall in September: 1.73"
The wettest month (with the highest rainfall) is May (2.76").
The driest month (with the least rainfall) is January (0.47").
Average rainfall days in September
Norwalk, IA
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is June (15.9 days).
The month with the least rainy days is February (3 days).
Average snowfall in September
Norwalk, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.24").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Norwalk, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Norwalk, IA
- Average daylight in September: 12h and 3min
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 12min).
- Average sunshine in September: 9h and 2min
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
Norwalk, IA
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is December (22.3 days).
The month with the least sunshine days is June (12.2 days).
Average UV index in September
Norwalk, 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
Norwalk, IA
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 54).
The months with the least cloud cover are July and September (Cloud cover 29).
Average visibility in September
Norwalk, IA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Norwalk, Iowa, USA
Weather forecast for your location
2. Allow the app to use your location
