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, Ottawa records an average high-temperature of a still moderately hot 74.1°F (23.4°C), marking a slight divergence from August's 79.2°F (26.2°C). An average low-temperature of 55.6°F (13.1°C) is expected during September.Humidity
In September, the average relative humidity is 79%.Rainfall
In Ottawa, in September, it is raining for 13.7 days, with typically 1.81" (46mm) of accumulated precipitation. Throughout the year, there are 161 rainfall days, and 27.24" (692mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 27min.On the first day of September, sunrise is at 7:03 am and sunset at 8:08 pm. On the last day of the month, sunrise is at 7:32 am and sunset at 7:19 pm EDT.
Sunshine
In September, the average sunshine is 7.7h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, a regular UV index of 4 translates into these guidelines:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature in Ottawa?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
Does it snow in September?
How many hours of daylight does Ottawa have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Ottawa have in September?
How high is the UV index in September?
Average temperature in September
Ottawa, OH
- Average high temperature in September: 74.1°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (31.1°F).
- Average low temperature in September: 55.6°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).
Average pressure in September
Ottawa, OH
- Average pressure in September: 30.04"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Ottawa, OH
- Average wind speed in September: 6.7mph
The windiest month (with the highest average wind speed) is January (10.6mph).
The calmest month (with the lowest average wind speed) is August (6mph).
Average humidity in September
Ottawa, OH
- Average humidity in September: 79%
The month with the highest relative humidity is February (84%).
The month with the lowest relative humidity is October (74%).
Average rainfall in September
Ottawa, OH
- Average rainfall in September: 1.81"
The wettest month (with the highest rainfall) is May (3.15").
The driest month (with the least rainfall) is February (1.65").
Average rainfall days in September
Ottawa, OH
- Average rainfall days in September: 13.7 days
The month with the highest number of rainy days is May (18.3 days).
The month with the least rainy days is January (7.1 days).
Average snowfall in September
Ottawa, OH
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.06").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Ottawa, OH
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (14.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Ottawa, OH
- 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 18min).
- Average sunshine in September: 7h and 4min
The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 18min).
Average sunshine days in September
Ottawa, OH
- Average sunshine days in September: 13.9 days
The month with the most sunshine days is November (16.2 days).
The month with the least sunshine days is February (9.3 days).
Average UV index in September
Ottawa, OH
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Ottawa, OH
- Average cloud cover in September: 38
The month with the most cloud cover is January (Cloud cover 65).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in September
Ottawa, OH
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, July, October, November and December (6mi).
The months with the lowest visibility are January, February, August and September (5mi).
Ottawa, Ohio, USA
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