Jackson
Wyoming, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Jackson, WY

A calm and clear river and vast green fields approaching the iconic white mountains within the Grand Teton National Park in Jackson, Wyoming
A calm and clear river and vast green fields approaching the iconic white mountains within the Grand Teton National Park in Jackson, Wyoming
September, the first month of the autumn, in Jackson, is still a comfortable month, with average temperature ranging between max 62.8°F (17.1°C) and min 32°F (0°C).

Temperature

In September, the average high-temperature decreases, from a pleasant 72.1°F (22.3°C) in August, to a comfortable 62.8°F (17.1°C). In Jackson, in September, the average low-temperature is 32°F (0°C).

Humidity

The average relative humidity in Jackson is 57%.

Rainfall

In Jackson, in September, it is raining for 10.8 days, with typically 1.77" (45mm) of accumulated precipitation. In Jackson, during the entire year, the rain falls for 103 days and collects up to 29.84" (758mm) of precipitation.

Snowfall

Months with snowfall in Jackson, Wyoming, are January through December. In Jackson, during September, snow falls for 3.3 days and regularly aggregates up to 5.12" (130mm) of snow. Throughout the year, in Jackson, Wyoming, there are 173.6 snowfall days, and 181.26" (4604mm) of snow is accumulated.

Daylight

In Jackson, Wyoming, the average length of the day is 12.5h.

Sunshine

The average sunshine in Jackson is 10h.

UV index

In Jackson, the average daily maximum UV index is 2. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from the exposure to the Sun's UV radiation for the ordinary person.
Note: The daily maximum UV index of 2 in September interpret into the following advice:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. 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. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the temperature in September in Jackson?

In Jackson, Wyoming, in September, the average high-temperature is 62.8°F (17.1°C), and the average low-temperature is 32°F (0°C).

What is the average humidity in September in Jackson?

The average relative humidity in September is 57%.

How much does it rain in Jackson in September?

In Jackson, Wyoming, in September, during 10.8 rainfall days, 1.77" (45mm) of precipitation is typically accumulated.

How much does it snow in Jackson in September?

In Jackson, Wyoming, during September, snow falls for 3.3 days and regularly aggregates up to 5.12" (130mm) of snow.

How many hours of daylight does Jackson have in September?

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

How long on average sun shines in September in Jackson?

In September, the average sunshine is 10h.

What is the UV index reading in September in Jackson?

The average daily maximum UV index in September in Jackson is 2. A UV Index of 2, and less, symbolizes a low health threat from the exposure to the Sun's UV rays.
Average temperature in September - Jackson, WY
  • Average high temperature in September: 62.8°F

The warmest month (with the highest average high temperature) is July (73.4°F).
The month with the lowest average high temperature is December (21.9°F).

  • Average low temperature in September: 0°F

Months with the highest average low temperature are January, February, March, April, May, June, July, August, September, October, November and December (0°F).
Coldest months (with the lowest average low temperature) are January, February, March, April, May, June, July, August, September, October, November and December (0°F).

Average humidity in September - Jackson, WY
  • Average humidity in September: 57%

The month with the highest relative humidity is February (94%).
The month with the lowest relative humidity is August (50%).

Average rainfall in September - Jackson, WY
  • Average rainfall in September: 1.77"

The wettest month (with the highest rainfall) is February (3.54").
The driest month (with the lowest rainfall) is August (1.34").

Average rainfall days in September - Jackson, WY
  • Average rainfall days in September: 10.8 days

The month with the highest number of rainy days is May (15.4 days).
The month with the lowest number of rainy days is January (2.9 days).

Average snowfall in September - Jackson, WY
  • Average snowfall in September: 5.12"

The month with the highest snowfall is February (29.33").
The month with the lowest snowfall is August (0.12").

Average snowfall days in September - Jackson, WY
  • Average snowfall days in September: 3.3 days

The month with the highest number of snowfall days is March (24.8 days).
The month with the lowest number of snowfall days is July (0.4 days).

Average daylight in September / Average sunshine in September - Jackson, WY
  • Average daylight in September: 12.5h

The month with the longest days is June (Average daylight: 15.4h).
The month with shortest days is December (Average daylight: 9h).

  • Average sunshine in September: 10h

The month with most sunshine is July (Average sunshine: 11.6h).
The month with least sunshine is February (Average sunshine: 3.4h).

Average UV index in September - Jackson, WY
  • Average UV index in September: 2

The month with the highest UV index is July (UV index 5).
Months with the lowest UV index are January, February, March, April, October, November and December (UV index 1).