September weather forecastDell, MT
September
Weather in September
The first month of the autumn, September, is still a comfortable month in Dell, Montana, with temperature in the range of an average low of 42.1°F (5.6°C) and an average high of 65.8°F (18.8°C).Temperature
Dell's progression into September includes a drop in the average high-temperature, from a warm 75.4°F (24.1°C) in August to a comfortable 65.8°F (18.8°C). Throughout September, Dell registers a distinct decrease from daytime highs, reaching an average low of 42.1°F (5.6°C).Humidity
In Dell, the average relative humidity in September is 48%.Rainfall
In September, the rain falls for 7.8 days. Throughout September, 0.75" (19mm) of precipitation is accumulated. Throughout the year, there are 103.2 rainfall days, and 9.84" (250mm) of precipitation is accumulated.Snowfall
January through June, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.9 snowfall days, it receives 1.22" (31mm) of snow. In Dell, during the entire year, snow falls for 81.9 days and aggregates up to 31.65" (804mm) of snow.Daylight
In September, the average length of the day is 12h and 30min.On the first day of the month, sunrise is at 6:54 am and sunset at 8:06 pm. On the last day of September, in Dell, sunrise is at 7:28 am and sunset at 7:12 pm MDT.
Sunshine
The average sunshine in September is 9.7h.UV index
In September, the average daily maximum UV index is 3. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum daily UV index of 3 in September interprets into the following recommendations:
Undertake protective steps - Obligation to safeguard skin and eyes from harm is in place. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat. 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
Dell, MT
- Average high temperature in September: 65.8°F
The warmest month (with the highest average high temperature) is July (76.6°F).
The month with the lowest average high temperature is December (24.3°F).
- Average low temperature in September: 42.1°F
The month with the highest average low temperature is July (47.1°F).
The coldest month (with the lowest average low temperature) is December (9.9°F).
Average pressure in September
Dell, MT
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.25"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Dell, MT
- Average wind speed in September: 5.8mph
The windiest months (with the highest average wind speed) are November and December (7.3mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in September
Dell, MT
- Average humidity in September: 48%
The months with the highest relative humidity are January and February (86%).
The months with the lowest relative humidity are July and August (43%).
Average rainfall in September
Dell, MT
- Average rainfall in September: 0.75"
The wettest month (with the highest rainfall) is June (1.73").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days in September
Dell, MT
- Average rainfall days in September: 7.8 days
The month with the highest number of rainy days is May (13.7 days).
The month with the least rainy days is January (4.6 days).
Average snowfall in September
Dell, MT
- Average snowfall in September: 1.22"
The month with the highest snowfall is April (4.96").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Dell, MT
- Average snowfall days in September: 0.9 days
The month with the highest number of snowfall days is February (13.3 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Dell, MT
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in September: 9h and 42min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 5h and 54min).
Average sunshine days in September
Dell, MT
- Average sunshine days in September: 18.4 days
The month with the most sunshine days is July (20.7 days).
The month with the least sunshine days is April (10.7 days).
Average UV index in September
Dell, MT
- Average UV index in September: 3
The month with the highest UV index is July (UV index 5).
The month with the lowest UV index is February (UV index 1).
Average cloud cover in September
Dell, MT
- Average cloud cover in September: 19
The month with the most cloud cover is February (Cloud cover 45).
The month with the least cloud cover is July (Cloud cover 13).
Average visibility in September
Dell, MT
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is February (4mi).
