Brighton
Colorado, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Brighton, CO

September, the first month of the autumn, in Brighton, is still a warm month, with average temperature ranging between max 79.7°F (26.5°C) and min 54°F (12.2°C).

Temperature

In September, the average high-temperature slightly decreases, from a hot 88.2°F (31.2°C) in August, to a warm 79.7°F (26.5°C). In Brighton, the average low-temperature is 54°F (12.2°C).

Humidity

In September, the average relative humidity in Brighton, Colorado, is 41%.

Rainfall

In September, in Brighton, Colorado, the rain falls for 7.2 days. Throughout September, 0.43" (11mm) of precipitation is accumulated. Throughout the year, in Brighton, there are 80.6 rainfall days, and 5.87" (149mm) of precipitation is accumulated.

Snowfall

June through September are months without snowfall.

Daylight

The average length of the day in Brighton, Colorado, is 12.4h.

Sunshine

In September, the average sunshine is 10.9h.

UV index

The average daily maximum UV index is 5. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to the UV radiation for average individuals.
Note: The daily maximum UV index of 5 in September interpret into the following advice:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun. 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 Brighton?

The average high-temperature, in September, in Brighton, is 79.7°F (26.5°C), while the average low-temperature is 54°F (12.2°C).

What is the average humidity in September in Brighton?

In Brighton, the average relative humidity in September is 41%.

How many days does it rain in September in Brighton?

In Brighton, Colorado, in September, it is raining for 7.2 days, with typically 0.43" (11mm) of accumulated precipitation.

Does it snow in Brighton in September?

In Brighton, Colorado, in September, it doesn't snow. In October, it regularly snows.

When it does not snow in Brighton?

In Brighton snow does not fall in June through September.

How many hours of daylight does Brighton have in September?

In Brighton, Colorado, the average length of the day in September is 12.4h.

How many hours of sunshine does Brighton have in September?

In September, the average sunshine in Brighton, Colorado, is 10.9h.

What is the UV index intensity in September in Brighton?

The average daily maximum UV index in September in Brighton, Colorado, is 5. A UV Index of 3 to 5 symbolizes a moderate vulnerability from the exposure to the Sun's UV rays.
Average temperature in September - Brighton, CO
  • Average high temperature in September: 79.7°F

The warmest month (with the highest average high temperature) is July (88.9°F).
The month with the lowest average high temperature is December (40.8°F).

  • Average low temperature in September: 54°F

The month with the highest average low temperature is July (61.9°F).
The coldest month (with the lowest average low temperature) is December (21.2°F).

Average humidity in September - Brighton, CO
  • Average humidity in September: 41%

Months with the highest relative humidity are January and February (64%).
The month with the lowest relative humidity is August (40%).

Average rainfall in September - Brighton, CO
  • Average rainfall in September: 0.43"

The wettest month (with the highest rainfall) is May (0.98").
The driest month (with the least rainfall) is December (0.12").

Average rainfall days in September - Brighton, CO
  • Average rainfall days in September: 7.2 days

The month with the highest number of rainy days is May (10.8 days).
The month with the least rainy days is December (2.6 days).

Average snowfall in September - Brighton, CO
  • Average snowfall in September: 0"

The month with the highest snowfall is February (1.89").
Months with the least snowfall are June, July, August and September (0").

Average snowfall days in September - Brighton, CO
  • Average snowfall days in September: 0.1 days

The month with the highest number of snowfall days is February (6.8 days).
Months with the least snowfall days are June, July and August (0 days).

Average daylight in September / Average sunshine in September - Brighton, CO
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 15h).
The month with the shortest days is December (Average daylight: 9.4h).

  • Average sunshine in September: 10.9h

Months with the most sunshine are June and July (Average sunshine: 11.8h).
The month with the least sunshine is February (Average sunshine: 6.6h).

Average UV index in September - Brighton, CO
  • Average UV index in September: 5

Months with the highest UV index are June, July and August (UV index 6).
Months with the lowest UV index are January, February, November and December (UV index 2).