Temperatures in September
It's pleasantly warm in September in Great Falls with an average temperature of 22°C. Temperatures this month range from a low of 17°C to a high of 28°C. At night, you can expect temperatures between 5°C and 11°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Great Falls in September. The red line indicates the max temperatures, and the blue line shows the minimums.
Start of September
The month of September starts in Great Falls with warm temperatures, averaging around 26°C during the day and nights close to 10°C. A few showers might pop up in the first days of the month, but the weather remains mostly sunny and dry.
Mid-September
By mid-September, the average daytime temperature drops to around 21°C, with nights close to 8°C. There might be a few showers during this period, but plenty of dry days with sunshine too.
End of September
By the end of September, the average daytime temperature in Great Falls will be around 21°C, with nights close to 7°C. A shower might show up, but overall the weather will be dry and sunny.
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Precipitation in September
In September, there is an average of 67 mm of precipitation, spread over 6 days. Of the total precipitation, about 1,6 cm falls as snow in September. The wind speed is around 4 Bft, mostly coming from the Southwest.
The average precipitation chance is 20% per day this month. Though that seems low, there are also a few days with a higher chance of precipitation.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in September for Great Falls. 0% means it never rained on that day in the past 10 years, and 100% means it rained every day. All values in between represent the average chance of precipitation on that day.
Great Falls in September |
London | ||
|---|---|---|---|
 Average Temperature |
22°C | 20°C | |
 High Temp |
28°C | 22°C | |
| Low Temp |
17°C | 17°C | |
 Total Precipitation |
67 mm | 44 mm | |
| Rainy Days |
6 days | 8 days | |
 Total Snowfall |
1,6 cm | 0 cm | |
| Snowy Days |
1 day | 0 days | |
August
UV index
The UV index is a maximum of 6 this month. That's a moderate to high value on the intensity scale of 1 to 11. Unprotected skin can burn within 15-25 minutes.
Is September a good time to visit Great Falls?
Want nice weather? Then September is a great time to be in Great Falls. You’ll have pleasant temperatures and not too much rain this month.
Temperature records for Great Falls in September
With 39°C, Great Falls hit the highest temperature in the last 10 years in September 2022. The lowest daytime temperature in this month was -2°C in 2019. The extreme night temperatures ranged from a low of -7°C to a high of 19°C.
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Daily Temperature in September in Great Falls
This chart shows the average daily temperatures, both day and night, for each day in September in Great Falls, measured in degrees Celsius. The red line represents the maximum temperatures, while the blue line shows the minimums. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, gives an overview of the average daily temperatures during this month.
Daily Precipitation in September in Great Falls
The chart below shows the average daily precipitation in September for Great Falls, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are shown at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that rain is more likely. But it’s still an average, so each day can be different. Based on historical weather data for September, you can expect around 6 days of rain in Great Falls.
Daily Snowfall in September in Great Falls
This chart shows the average daily snowfall in September in Great Falls, measured in centimetres. The bottom of the chart shows the days of the month. The data is based on historical measurements and gives an idea of the average snowfall in September.
Daily UV Index in September in Great Falls
This chart shows the average daily UV index in September in Great Falls, 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.
Temperature in September in Great Falls Over the Years
This chart shows the average temperature in September in Great Falls, measured in degrees Celsius, over the past years.
Total Precipitation in September in Great Falls Over the Years
This chart shows the average precipitation in September in Great Falls, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Snowfall in September in Great Falls per year
This chart shows the average snowfall in September in Great Falls, measured in centimetres, over the past years.
Daily climate in September for Great Falls
Click on a specific day in September for detailed info on the typical weather on that day in Great Falls. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Great Falls
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Average Weather in Great Falls by Month
Click on a month below to see detailed weather info for Great Falls. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of Great Falls for all months at once
