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
Saint John's transition into September involves a shift in temperature, receding from a warm 83.8°F (28.8°C) in August to a pleasant 72.9°F (22.7°C). The nights of September anticipate an average low-temperature of 53.2°F (11.8°C).Humidity
In Saint John, the average relative humidity in September is 45%.Rainfall
In Saint John, in September, it is raining for 5.6 days, with typically 0.24" (6mm) of accumulated precipitation. Throughout the year, there are 84.3 rainfall days, and 7.24" (184mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, September, November and December. September is the first month it typically snows. Throughout September, in the average 0.1 snowfall days, it receives 0.04" (1mm) of snow. Throughout the year, there are 32.5 snowfall days, and 14.09" (358mm) of snow is accumulated.Daylight
The average length of the day in September is 12h and 32min.On the first day of the month, sunrise is at 6:10 am and sunset at 7:29 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:31 pm PDT.
Sunshine
The average sunshine in September is 10.4h.UV index
In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: The UV index of 4 during September leads to these advisories:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Take careful note! The UV radiation of the Sun can be nearly doubled by snow reflection.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures?
What is the average humidity in September in Saint John?
How many days does it rain in September?
When does it start snowing in Saint John?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Saint John, WA
- Average high temperature in September: 72.9°F
The warmest month (with the highest average high temperature) is July (84.4°F).
The month with the lowest average high temperature is December (33.1°F).
- Average low temperature in September: 53.2°F
The month with the highest average low temperature is August (61.3°F).
The coldest month (with the lowest average low temperature) is December (23.9°F).
Average pressure in September
Saint John, WA
- Average pressure in September: 29.95"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is August (29.9"Hg).
Average wind speed in September
Saint John, WA
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is March (8.8mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in September
Saint John, WA
- Average humidity in September: 45%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is August (36%).
Average rainfall in September
Saint John, WA
- Average rainfall in September: 0.24"
The wettest months (with the highest rainfall) are January and May (0.91").
The driest month (with the least rainfall) is July (0.16").
Average rainfall days in September
Saint John, WA
- Average rainfall days in September: 5.6 days
The month with the highest number of rainy days is March (10.1 days).
The month with the least rainy days is July (3.5 days).
Average snowfall in September
Saint John, WA
- Average snowfall in September: 0.04"
The month with the highest snowfall is February (3.82").
The months with the least snowfall are June, July, August and October (0").
Average snowfall days in September
Saint John, WA
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is December (9.3 days).
The months with the least snowfall days are June, July, August and October (0 days).
Average daylight in September /
Average sunshine in September
Saint John, 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: 10h and 2min
The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 4h and 18min).
Average sunshine days in September
Saint John, WA
- Average sunshine days in September: 23.6 days
The month with the most sunshine days is July (26.6 days).
The month with the least sunshine days is February (15.9 days).
Average UV index in September
Saint John, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Saint John, WA
- Average cloud cover in September: 19
The months with the most cloud cover are January and December (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 11).
Average visibility in September
Saint John, WA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (5mi).
Saint John, Washington, USA
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