September weather forecast
Three Forks, MT

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Weather in September

September, the first month of the autumn in Three Forks, is also an agreeable month, with temperature in the range of an average high of 70.9°F (21.6°C) and an average low of 44.4°F (6.9°C).

Temperature

September's onset brings a reduction in the average high-temperature, from a moderately hot 81.9°F (27.7°C) in August to a pleasant 70.9°F (21.6°C). Three Forks records a marked divergence from the day's high temperatures, with nights in September averaging at a chilly 44.4°F (6.9°C).

Humidity

In September, the average relative humidity is 49%.

Rainfall

In Three Forks, in September, it is raining for 8.4 days, with typically 0.91" (23mm) of accumulated precipitation. Throughout the year, in Three Forks, there are 134.2 rainfall days, and 11.34" (288mm) 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 0.5 snowfall days, it receives 0.83" (21mm) of snow. In Three Forks, during the entire year, snow falls for 79.6 days and aggregates up to 30.08" (764mm) of snow.

Daylight

The average length of the day in September in Three Forks, Montana, is 12h and 31min.
On the first day of the month, sunrise is at 6:48 am and sunset at 8:03 pm. On the last day of September, sunrise is at 7:24 am and sunset at 7:07 pm MDT.

Sunshine

In September, the average sunshine is 10h.

UV index

The average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for average individuals.
Note: During September, 3 as the daily maximum UV index converts into the following advice:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. The midday Sun can be dangerous due to its intense radiation; always find shade and reduce exposure. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Mark this! Snow reflection can nearly double the UV radiation intensity from the Sun.
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Frequently asked questions

What is the usual temperature for Three Forks in September?

September temperatures in Three Forks, Montana, vary between a high-temperature of 70.9°F (21.6°C) and a low-temperature of 44.4°F (6.9°C). In August, the average heat index (a.k.a. 'apparent temperature', 'feels like'), which calculates the temperature value influenced by the moisture in the air, is appraised at 82.4°F (28°C).

What is the average humidity in September in Three Forks?

The average relative humidity in September is 49%.

How much does it rain in Three Forks in September?

In Three Forks, Montana, in September, during 8.4 rainfall days, 0.91" (23mm) of precipitation is typically accumulated.

When does it start snowing in Three Forks?

September is the first month it typically snows in Three Forks. Throughout September, in the average 0.5 snowfall days, it receives 0.83" (21mm) of snow.

What is the average length of the day in September in Three Forks?

In September, the average day length in Three Forks is 12h and 31min.

What time are sunrise and sunset in September in Three Forks?

In September, on the first day of the month, sunrise is at 6:48 am and sunset at 8:03 pm. On the last day of the month, in Three Forks, sunrise is at 7:24 am and sunset at 7:07 pm MDT.

How many hours of sunshine does Three Forks have in September?

In September, the average sunshine duration in Three Forks is 10h.

What is the UV index reading in September in Three Forks?

In Three Forks, the average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a medium health risk from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Three Forks, MT

Average temperature in September - Three Forks, MT
  • Average high temperature in September: 70.9°F

The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is December (28°F).

  • Average low temperature in September: 44.4°F

The month with the highest average low temperature is August (50.5°F).
The coldest month (with the lowest average low temperature) is December (12.7°F).

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Average pressure in September
Three Forks, MT

Average pressure in September - Three Forks, MT
  • Average pressure in September: 29.98"Hg

The months with the highest atmospheric pressure are January and December (30.19"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).

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Average wind speed in September
Three Forks, MT

Average wind speed in September - Three Forks, MT
  • Average wind speed in September: 4.6mph

The windiest month (with the highest average wind speed) is April (5.5mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).

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Average humidity in September
Three Forks, MT

Average humidity in September - Three Forks, MT
  • Average humidity in September: 49%

The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is August (44%).

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Average rainfall in September
Three Forks, MT

Average rainfall in September - Three Forks, MT
  • Average rainfall in September: 0.91"

The wettest month (with the highest rainfall) is June (1.57").
The driest month (with the least rainfall) is August (0.51").

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Average rainfall days in September
Three Forks, MT

Average rainfall days in September - Three Forks, MT
  • Average rainfall days in September: 8.4 days

The month with the highest number of rainy days is April (16.5 days).
The month with the least rainy days is August (7.6 days).

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Average snowfall in September
Three Forks, MT

Average snowfall in September - Three Forks, MT
  • Average snowfall in September: 0.83"

The month with the highest snowfall is February (6.02").
The months with the least snowfall are July and August (0").

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Average snowfall days in September
Three Forks, MT

Average snowfall days in September - Three Forks, MT
  • Average snowfall days in September: 0.5 days

The month with the highest number of snowfall days is February (16.5 days).
The months with the least snowfall days are July and August (0 days).

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Average daylight in September /
Average sunshine in September
Three Forks, MT

Average daylight in September / Average sunshine in September - Three Forks, MT
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).

  • Average sunshine in September: 10h and 0min

The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 5h and 54min).

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Average sunshine days in September
Three Forks, MT

Average sunshine days in September - Three Forks, MT
  • Average sunshine days in September: 18.7 days

The month with the most sunshine days is September (18.7 days).
The month with the least sunshine days is April (9.3 days).

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Average UV index in September
Three Forks, MT

Average UV index in September - Three Forks, MT
  • Average UV index in September: 3

The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).

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Average cloud cover in September
Three Forks, MT

Average cloud cover in September - Three Forks, MT
  • Average cloud cover in September: 20

The month with the most cloud cover is February (Cloud cover 43).
The month with the least cloud cover is August (Cloud cover 13).

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Average visibility in September
Three Forks, MT

Average visibility in September - Three Forks, MT
  • Average visibility in September: 6mi

The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).

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Three Forks, Montana, USA

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