September weather forecastSaint John, ND
September
Weather in September
September, the first month of the autumn in Saint John, is also an enjoyable month, with an average temperature ranging between min 49.1°F (9.5°C) and max 67.6°F (19.8°C).Temperature
The onset of September is marked by a decrease in temperature, transitioning from a warm 77.9°F (25.5°C) in August to a refreshing 67.6°F (19.8°C). Saint John observes an average nighttime low-temperature of 49.1°F (9.5°C) during the month of September.Humidity
In September, the average relative humidity is 62%.Rainfall
In September, the rain falls for 11.3 days. Throughout September, 2.01" (51mm) of precipitation is accumulated. Throughout the year, there are 110.9 rainfall days, and 17.95" (456mm) of precipitation is accumulated.Snowfall
In Saint John, snow does not fall in June through September.Daylight
The average length of the day in September is 12h and 34min.On the first day of September, sunrise is at 6:56 am and sunset at 8:20 pm. On the last day of the month, sunrise is at 7:38 am and sunset at 7:18 pm CDT.
Sunshine
In September, the average sunshine is 8.5h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for average individuals.Note: A daily high UV index of 4 in September leads to these guidelines:
Be vigilant - A duty to shield skin and eyes from injury exists. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Saint John, ND
- Average high temperature in September: 67.6°F
The warmest month (with the highest average high temperature) is August (77.9°F).
The month with the lowest average high temperature is January (14.2°F).
- Average low temperature in September: 49.1°F
The month with the highest average low temperature is July (57.2°F).
The coldest month (with the lowest average low temperature) is January (0.5°F).
Average pressure in September
Saint John, ND
- Average pressure in September: 29.95"Hg
The month with the highest atmospheric pressure is February (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Saint John, ND
- Average wind speed in September: 9.8mph
The windiest month (with the highest average wind speed) is October (11mph).
The calmest month (with the lowest average wind speed) is August (8.5mph).
Average humidity in September
Saint John, ND
- Average humidity in September: 62%
The month with the highest relative humidity is January (93%).
The month with the lowest relative humidity is August (60%).
Average rainfall in September
Saint John, ND
- Average rainfall in September: 2.01"
The wettest month (with the highest rainfall) is June (3.27").
The driest month (with the least rainfall) is February (0.43").
Average rainfall days in September
Saint John, ND
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is June (18.8 days).
The month with the least rainy days is February (2 days).
Average snowfall in September
Saint John, ND
- Average snowfall in September: 0"
The month with the highest snowfall is November (4.29").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Saint John, ND
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (15.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Saint John, ND
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 18min).
- Average sunshine in September: 8h and 30min
The month with the most sunshine is July (Average sunshine: 11h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 6min).
Average sunshine days in September
Saint John, ND
- Average sunshine days in September: 16.8 days
The month with the most sunshine days is September (16.8 days).
The month with the least sunshine days is June (8.1 days).
Average UV index in September
Saint John, ND
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February and December (UV index 1).
Average cloud cover in September
Saint John, ND
- Average cloud cover in September: 30
The month with the most cloud cover is February (Cloud cover 70).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in September
Saint John, ND
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February, March and December (5mi).





