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United StatesThe weather in September in West Yellowstone
It's pleasantly warm in September in West Yellowstone with an average temperature of 19°C. Temperatures this month range from a low of 11°C to a high of 23°C. At night, you can expect temperatures between -6°C and 5°C.
Average temperatures and precipitation
This chart shows the average daily maximum and minimum temperatures (in degrees Celsius) and precipitation (in millimeters) in September for West Yellowstone, Montana. A low precipitation value usually indicates little to no rainfall on that day in recent years, while a higher value suggests more frequent rainfall.
Temperature records
With 31°C in 2022, West Yellowstone reached the highest temperature in September over the past 10 years. The lowest daytime temperature in this month was 2°C in 2019. The extreme nighttime temperatures ranged from a lowest recorded value of -12°C to a highest value of 12°C.
Precipitation and snowfall
In September, there is an average of 65 mm of precipitation, spread over 8 days. Of the total precipitation, about 4,1 cm falls as snow in September. The wind speed is around 4 Bft, mostly coming from the Southwest.
Daily weather in September for West Yellowstone
Click on any day in September to get detailed info about the usual weather on that day in West Yellowstone. Check out the historical temperatures and precipitation over the past 10 years on this day.
September weather comparison
| West Yellowstone | New York | |
|---|---|---|
| Average temperature | 19°C | 27°C |
| Max. temperature | 23°C | 31°C |
| Min. temperature | -6°C | -5°C |
| Total precipitation | 65 mm | 57 mm |
| Rainy days | 8 days | 9 days |
| Total snowfall | 4,1 cm | 0 cm |
| Snowy days | 3 days | 0 days |
Start of September
The month of September starts in West Yellowstone with mild temps, averaging around 21°C during the day and nights around 1°C.
Mid September
By mid-September, daytime temps drop to around 19°C, with nights around 0°C. There’s a chance of some showers during this time, but plenty of dry and sunny days too.
End of September
By the end of September, the average daytime temperature in West Yellowstone is around 17°C, while nighttime temps are about 2°C. A shower might pop up, but overall, the weather will be dry and sunny.
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UV index
The UV index is a maximum of 8 this month. That's a very high value on the intensity scale of 1 to 11. Unprotected skin can burn within 10-15 minutes.
Check out the climate of West Yellowstone for all months and discover the best travel time
Temperature charts
These charts show the average temperatures in September in West Yellowstone, Montana. The temperatures are shown in degrees Celsius and are calculated based on data from the past 10 years.
Daily Temperature in September in West Yellowstone
Temperature in September in West Yellowstone over the years
Precipitation charts
These charts show the average amount of precipitation in September in West Yellowstone, Montana. Precipitation is always measured as water, even when it falls as snow or hail The amount of precipitation is displayed in millimeters, while snowfall is shown in centimeters.
Daily Precipitation in September in West Yellowstone
Total precipitation in September in West Yellowstone over the years
Daily Snowfall in September in West Yellowstone
Snowfall in September in West Yellowstone per year
Daily UV index in September in West Yellowstone
This chart shows the average daily UV index in September in West Yellowstone, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Weather experiences in September in West Yellowstone
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Average weather in West Yellowstone by month
Click on a month below to see detailed weather info for West Yellowstone. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.