September weather forecastNorris, MT
September
Weather in September
September, the first month of the autumn in Norris, is also an enjoyable month, with an average temperature varying between 63.5°F (17.5°C) and 39.9°F (4.4°C).Temperature
The shift from August to September involves a decrease in the average high-temperature, dropping from a pleasant 73°F (22.8°C) to a comfortable 63.5°F (17.5°C). Norris experiences a significant downturn from peak daytime temperatures throughout September, with the average low-temperature dipping to a wintry 39.9°F (4.4°C).Humidity
In Norris, the average relative humidity in September is 56%.Rainfall
In September, the rain falls for 10.3 days. Throughout September, 1.61" (41mm) of precipitation is accumulated. In Norris, during the entire year, the rain falls for 105.7 days and collects up to 17.99" (457mm) of precipitation.Snowfall
Months with snowfall are January through December. In September, it is snowing for 3.9 days. Throughout September, 4.37" (111mm) of snow is accumulated. In Norris, during the entire year, snow falls for 136.1 days and aggregates up to 86.93" (2208mm) of snow.Daylight
The average length of the day in September is 12h and 31min.On the first day of the month, sunrise is at 6:49 am and sunset at 8:03 pm. On the last day of September, in Norris, sunrise is at 7:24 am and sunset at 7:08 pm MDT.
Sunshine
In September, the average sunshine is 9.7h.UV index
In Norris, the average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: The daily maximum UV index of 3 in September interprets into the following advice:
Undertake protective steps - Preventing sun damage is advised. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. 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. Keep in mind! Snow's reflective quality can nearly double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Norris, MT
- Average high temperature in September: 63.5°F
The warmest month (with the highest average high temperature) is July (74.5°F).
The month with the lowest average high temperature is December (22.3°F).
- Average low temperature in September: 39.9°F
The month with the highest average low temperature is August (46°F).
The coldest month (with the lowest average low temperature) is December (7.7°F).
Average pressure in September
Norris, MT
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.22"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Norris, MT
- Average wind speed in September: 5.3mph
The windiest month (with the highest average wind speed) is January (7.1mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in September
Norris, MT
- Average humidity in September: 56%
The month with the highest relative humidity is February (90%).
The month with the lowest relative humidity is August (50%).
Average rainfall in September
Norris, MT
- Average rainfall in September: 1.61"
The wettest month (with the highest rainfall) is May (2.36").
The driest month (with the least rainfall) is December (0.75").
Average rainfall days in September
Norris, MT
- Average rainfall days in September: 10.3 days
The month with the highest number of rainy days is June (16.5 days).
The month with the least rainy days is November (2.9 days).
Average snowfall in September
Norris, MT
- Average snowfall in September: 4.37"
The month with the highest snowfall is April (14.76").
The month with the least snowfall is August (0.08").
Average snowfall days in September
Norris, MT
- Average snowfall days in September: 3.9 days
The month with the highest number of snowfall days is April (19.9 days).
The month with the least snowfall days is August (0.3 days).
Average daylight in September /
Average sunshine in September
Norris, MT
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in September: 9h and 42min
The month with the most sunshine is July (Average sunshine: 11h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in September
Norris, MT
- Average sunshine days in September: 14.5 days
The month with the most sunshine days is January (16.3 days).
The month with the least sunshine days is April (6.9 days).
Average UV index in September
Norris, MT
- 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 and February (UV index 1).
Average cloud cover in September
Norris, MT
- Average cloud cover in September: 23
The month with the most cloud cover is February (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 17).
Average visibility in September
Norris, MT
- Average visibility in September: 6mi
The months with the highest visibility are June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (4mi).
