Columbus
Montana, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Columbus, MT

September, the first month of the autumn, in Columbus, is also an agreeable month, with average temperature varying between 72°F (22.2°C) and 50°F (10°C).

Temperature

In September, the average high-temperature decreases, from a moderately hot 81.1°F (27.3°C) in August, to an agreeable 72°F (22.2°C). In September, the average low-temperature is 50°F (10°C).

Humidity

In September, the average relative humidity is 45%.

Rainfall

In Columbus, in September, it is raining for 7.8 days, with typically 0.79" (20mm) of accumulated precipitation. In Columbus, during the entire year, the rain falls for 125.4 days and collects up to 14.49" (368mm) of precipitation.

Snowfall

Months with snowfall in Columbus are January through May, September through December. September is the first month it typically snows in Columbus. Throughout September, in the average 0.3 snowfall days, it receives 0.24" (6mm) of snow. In Columbus, during the entire year, snow falls for 63.3 days, and aggregates up to 39.09" (993mm) of snow.

Daylight

The average length of the day in September is 12.5h.

Sunshine

In Columbus, the average sunshine is 10.5h.

UV index

The average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to the UV radiation for the ordinary person.
Note: In September, the average maximum UV index of 4 translate into the following recommendations:
Take precautions - Protection against sun damage is advised. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the temperature in September in Columbus?

In Columbus, in September, the average high-temperature is 72°F (22.2°C), and the average low-temperature is 50°F (10°C).

What is the average humidity in September in Columbus?

In Columbus, the average relative humidity in September is 45%.

How many days does it rain in September in Columbus?

In Columbus, in September, during 7.8 rainfall days, 0.79" (20mm) of precipitation is typically accumulated.

When does it start snowing in Columbus?

September is the first month it typically snows. Throughout September, in the average 0.3 snowfall days, it receives 0.24" (6mm) of snow.

How many hours of daylight does Columbus have in September?

In September, the average length of the day is 12.5h.

How long on average sun shines in September in Columbus?

In September, the average sunshine in Columbus is 10.5h.

What is the UV index intensity in September in Columbus?

In Columbus, Montana, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium health risk from the exposure to the Sun's UV rays.
Average temperature in September - Columbus, MT
  • Average high temperature in September: 72°F

The warmest month (with the highest average high temperature) is July (82.6°F).
The month with the lowest average high temperature is December (30.9°F).

  • Average low temperature in September: 50°F

The month with the highest average low temperature is August (57.2°F).
The coldest month (with the lowest average low temperature) is February (17.4°F).

Average humidity in September - Columbus, MT
  • Average humidity in September: 45%

The month with the highest relative humidity is January (76%).
The month with the lowest relative humidity is August (41%).

Average rainfall in September - Columbus, MT
  • Average rainfall in September: 0.79"

The wettest month (with the highest rainfall) is May (2.6").
The driest month (with the least rainfall) is January (0.63").

Average rainfall days in September - Columbus, MT
  • Average rainfall days in September: 7.8 days

The month with the highest number of rainy days is May (17.5 days).
The month with the least rainy days is February (6.7 days).

Average snowfall in September - Columbus, MT
  • Average snowfall in September: 0.24"

The month with the highest snowfall is February (7.36").
Months with the least snowfall are June, July and August (0").

Average snowfall days in September - Columbus, MT
  • Average snowfall days in September: 0.3 days

The month with the highest number of snowfall days is February (13.4 days).
Months with the least snowfall days are June, July and August (0 days).

Average daylight in September / Average sunshine in September - Columbus, MT
  • Average daylight in September: 12.5h

The month with the longest days is June (Average daylight: 15.7h).
The month with the shortest days is December (Average daylight: 8.8h).

  • Average sunshine in September: 10.5h

The month with the most sunshine is July (Average sunshine: 12h).
Months with the least sunshine are February and December (Average sunshine: 6.2).

Average UV index in September - Columbus, MT
  • Average UV index in September: 4

The month with the highest UV index is July (UV index 6).
Months with the lowest UV index are January, February, March, November and December (UV index 2).