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
Onalaska's weather in September involves a mild decrease in the average high-temperature, moving down slightly from August's warm 76.6°F (24.8°C) to a pleasant 69.6°F (20.9°C). September's nights exhibit a sharp contrast from day highs, with an average temperature of 46°F (7.8°C).Humidity
In Onalaska, the average relative humidity in September is 78%.Rainfall
In Onalaska, in September, during 10.6 rainfall days, 1.18" (30mm) of precipitation is typically accumulated. In Onalaska, during the entire year, the rain falls for 170.1 days and collects up to 22.56" (573mm) of precipitation.Snowfall
April through October are months without snowfall in Onalaska.Daylight
The average length of the day in September is 12h and 32min.On the first day of the month, sunrise is at 6:32 am and sunset at 7:49 pm. On the last day of September, in Onalaska, Washington, sunrise is at 7:09 am and sunset at 6:51 pm PDT.
Sunshine
The average sunshine in September is 8.4h.UV index
In Onalaska, the average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: In September, a daily maximum UV index of 3 leads to the following instructions:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. Midday is when the Sun's radiation is strongest; avoid prolonged exposure during this time. 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
What are the temperatures in Onalaska in September?
What is the average humidity in September in Onalaska?
How many days does it rain in September in Onalaska?
When it does not snow in Onalaska?
How many hours of daylight does Onalaska have in September?
When are sunrise and sunset in September in Onalaska?
How many hours of sunshine does Onalaska have in September?
What is the UV index intensity in September in Onalaska?
Average temperature in September
Onalaska, WA
- Average high temperature in September: 69.6°F
The warmest month (with the highest average high temperature) is August (76.6°F).
The month with the lowest average high temperature is December (42.3°F).
- Average low temperature in September: 46°F
The month with the highest average low temperature is August (48.6°F).
The coldest month (with the lowest average low temperature) is December (32.4°F).
Average pressure in September
Onalaska, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are August and September (30.01"Hg).
Average wind speed in September
Onalaska, WA
- Average wind speed in September: 3.5mph
The windiest month (with the highest average wind speed) is January (4.8mph).
The calmest months (with the lowest average wind speed) are August and September (3.5mph).
Average humidity in September
Onalaska, WA
- Average humidity in September: 78%
The months with the highest relative humidity are January, February, November and December (88%).
The month with the lowest relative humidity is July (73%).
Average rainfall in September
Onalaska, WA
- Average rainfall in September: 1.18"
The wettest month (with the highest rainfall) is January (3.54").
The driest months (with the least rainfall) are July and August (0.39").
Average rainfall days in September
Onalaska, WA
- Average rainfall days in September: 10.6 days
The month with the highest number of rainy days is March (19.4 days).
The month with the least rainy days is August (6.1 days).
Average snowfall in September
Onalaska, WA
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.81").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Onalaska, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Onalaska, WA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in September: 8h and 2min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The months with the least sunshine are January, February and December (Average sunshine: 3h and 42min).
Average sunshine days in September
Onalaska, WA
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is August (22.1 days).
The month with the least sunshine days is February (9 days).
Average UV index in September
Onalaska, WA
- Average UV index in September: 3
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Onalaska, WA
- Average cloud cover in September: 45
The months with the most cloud cover are February and March (Cloud cover 64).
The month with the least cloud cover is August (Cloud cover 37).
Average visibility in September
Onalaska, WA
- Average visibility in September: 4mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (4mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (4mi).
Onalaska, Washington, USA
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