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Hourly Forecast
Daylight Hours
07:10
Sunrise
19:29
Sunset
Moon
Waxing Crescent
12:32
Moonrise
20:42
Moonset
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Weather in Great Falls today, September 15, 2026
Expect a mostly clear day in Great Falls on September 15, 2026, with sunshine dominating from morning through evening. Cloud should stay limited, so the overall feel remains bright and settled. Cloud leads the morning, peaking close to 100% near 07:00. Sunshine has little room until later in the day.
Expect highs of 20°C and cooler readings close to 7°C. Moisture in the air spans 30%-90%, with the highest values around 07:00. Winds stay light, near 10.8 km/h by 21:00, so the day feels still more than breezy.
Expect persistent cloud later on, with amounts around 100% by 12:00. Sunshine remains the exception, not the rule. Visibility stays near 16.1 km. The sun rises at 07:10 and sets at 19:29, for a total of 12 hours 19 minutes of sunlight today.
The practical takeaway for Great Falls is a bright September 15, 2026, ideal for outdoor errands before temperatures ease from about 20°C.
Frequently asked questions about weather in Great Falls
How warm does it get in Great Falls?
The warmest month in Great Falls is July, with average high temperatures of 31°C. The average temperature during this period is around 22°C.
How cold does it get in Great Falls?
The coldest month in Great Falls is February, with average low temperatures of -9°C. The average temperature during this period is around -5°C.
What is the wettest time of year in Great Falls?
The wettest month in Great Falls is May, with an average of 66mm of precipitation.
What is the driest time of year in Great Falls?
The driest month in Great Falls is July, with an average of 20mm of precipitation.
