Rocky Mountain National Park (CO)
September
Weather in Rocky Mountain National Park, Colorado for September 2026
Your guide to Rocky Mountain National Park weather in September - trends and predictions
In general, the average temperature in Rocky Mountain National Park at the beginning of September is 18 °F. As the month progressed, temperatures tended to moderately fall, reaching an average of 16 °F by the end of September.
The climate of Rocky Mountain National Park in September is notably wet, with an average of 12 rainy days, and a total of 94.7 mm of precipitation.
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Temperatures
Rain 🌧️
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18
Dry days
12
Rainy days
0
Snow days
17°/9°
Temperatures
15 km/h
Avg max wind
54 %
Avg humidity
Rocky Mountain National Park Weather September
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Temperatures trend during September in Rocky Mountain National Park
See the weather trend as well as the moving average line
September weather in Rocky Mountain National Park day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 19° /10° | 0 mm | 5 | |
| Sept. 2 |  Thundery outbreaks possible | 19° /11° | 0 mm | 4 | |
| Sept. 3 |  Cloudy | 19° /12° | 0 mm | 4 | |
| Sept. 4 | Cloudy | 23° /12° | 0 mm | 5 | |
| Sept. 5 | Cloudy | 13° /7° | 0 mm | 3 | |
| Sept. 6 | Thundery outbreaks possible | 14° /8° | 0 mm | 3 | |
| Sept. 7 | Thundery outbreaks possible | 19° /11° | 0 mm | 4 | |
| Sept. 8 | Thundery outbreaks possible | 19° /11° | 0 mm | 4 | |
| Sept. 9 | Thundery outbreaks possible | 20° /12° | 0 mm | 5 | |
| Sept. 10 | Thundery outbreaks possible | 22° /12° | 0 mm | 5 | |
| Sept. 11 | Thundery outbreaks possible | 19° /13° | 1.5 mm | 4 | |
| Sept. 12 | Thundery outbreaks possible | 18° /11° | 4.6 mm | 4 | |
| Sept. 13 |  Light rain shower | 16° /9° | 4.4 mm | 4 | |
| Sept. 14 |  Moderate rain | 15° /5° | 12.9 mm | 4 | |
| Sept. 15 |  Partly cloudy | 19° /9° | 0 mm | 5 | |
| Sept. 16 | Light rain shower | 16° /9° | 3.2 mm | 4 | |
| Sept. 17 | Light rain shower | 13° /7° | 13.2 mm | 3 | |
| Sept. 18 | Thundery outbreaks possible | 10° /6° | 0 mm | 3 | |
| Sept. 19 | Cloudy | 18° /7° | 0 mm | 4 | |
| Sept. 20 | Light rain shower | 17° /10° | 8.5 mm | 4 | |
| Sept. 21 | Thundery outbreaks possible | 17° /10° | 0 mm | 4 | |
| Sept. 22 |  Patchy light rain with thunder | 17° /7° | 3.8 mm | 4 | |
| Sept. 23 |  Light sleet showers | 10° /5° | 15.9 mm | 3 | |
| Sept. 24 |  Overcast | 12° /3° | 3.1 mm | 3 | |
| Sept. 25 | Sunny | 19° /6° | 0 mm | 5 | |
| Sept. 26 | Partly cloudy | 19° /9° | 0 mm | 5 | |
| Sept. 27 | Thundery outbreaks possible | 16° /9° | 0 mm | 4 | |
| Sept. 28 |  Moderate or heavy rain shower | 15° /10° | 19.9 mm | 4 | |
| Sept. 29 | Thundery outbreaks possible | 15° /11° | 3.7 mm | 4 | |
| Sept. 30 | Thundery outbreaks possible | 16° /8° | 0 mm | 4 | |
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Important Notice
Our weather forecast for Rocky Mountain National Park in September is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Rocky Mountain National Park forecast closer to your planned date for the most up-to-date weather information.
Change Month
Rocky Mountain National Park in September - FAQ
What are the expected maximum and minimum temperatures in Rocky Mountain National Park during September?
Enjoy moderate daytime temperatures of up to 17° and cooler nights around 9°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Rocky Mountain National Park during September?
Moderate rainfall is anticipated in Rocky Mountain National Park during September, with a total of 94.7 mm spread over approximately 12 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Rocky Mountain National Park during September?
The average wind speed in Rocky Mountain National Park during September is 15 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Rocky Mountain National Park
Explore the daily rainfall trends and prepare for Rocky Mountain National Parks September weather 💧
UV exposure in Rocky Mountain National Park during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Rocky Mountain National Park?Get accurate weather forecasts for Rocky Mountain National Park, located at latitude 40.343 and longitude -105.684. Stay updated with localized weather information tailored for Rocky Mountain National Park.
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