Mono County (Mammoth Lakes)
September
Weather in Mono County for September 2025
Your guide to Mono County weather in September - trends and predictions
Snowfall in Mono County during September is quite rare, with fewer than 2 snowy days on average.
In general, the average temperature in Mono County at the beginning of September is 24 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 20.6 °F by the end of September.
With an average of 2 rainy days, Mono County experiences minimal rainfall in September.
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Snow Forecast ❄️
Temperatures
Rain 🌧️
More
27
Dry days
2
Rainy days
1
Snow days
20°/6°
Temperatures
18 km/h
Avg max wind
36 %
Avg humidity
Mono County Weather September
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| Sun. | Mon. | Tue. | Wed. | Thu. | Fri. | Sat. |
|---|---|---|---|---|---|---|
| 1  23° | 2 22° | 3 23° | 4  25° | 5  26° | 6 25° | |
| 7 24° | 8 23° | 9 22° | 10  22° | 11 21° | 12 20° | 13 22° |
| 14  21° | 15 17° | 16  8° | 17 13° | 18  12° | 19  10° | 20 15° |
| 21 17° | 22 18° | 23 19° | 24 20° | 25 19° | 26 21° | 27 22° |
| 28 22° | 29 21° | 30 19° |
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Temperatures trend during September in Mono County
See the weather trend as well as the moving average line
September weather day by day
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| Date | Weather | Temperatures | Rain | Snow | More |
|---|---|---|---|---|---|
| Sept. 1 | Sunny | 23° /9° | 0 mm | 0 cm | |
| Sept. 2 | Sunny | 22° /8° | 0 mm | 0 cm | |
| Sept. 3 | Sunny | 23° /7° | 0 mm | 0 cm | |
| Sept. 4 | Partly cloudy | 25° /8° | 0 mm | 0 cm | |
| Sept. 5 | Patchy rain possible | 26° /10° | 0.1 mm | 0 cm | |
| Sept. 6 | Patchy rain possible | 25° /11° | 0 mm | 0 cm | |
| Sept. 7 | Partly cloudy | 24° /10° | 0 mm | 0 cm | |
| Sept. 8 | Sunny | 23° /9° | 0 mm | 0 cm | |
| Sept. 9 | Sunny | 22° /8° | 0 mm | 0 cm | |
| Sept. 10 | Overcast | 22° /6° | 0 mm | 0 cm | |
| Sept. 11 | Sunny | 21° /3° | 0 mm | 0 cm | |
| Sept. 12 | Sunny | 20° /1° | 0 mm | 0 cm | |
| Sept. 13 | Sunny | 22° /3° | 0 mm | 0 cm | |
| Sept. 14 | Cloudy | 21° /6° | 0 mm | 0 cm | |
| Sept. 15 | Sunny | 17° /2° | 0 mm | 0 cm | |
| Sept. 16 | Light snow showers | 8° /-1° | 0.8 mm | 0.3 cm | |
| Sept. 17 | Partly cloudy | 13° /-1° | 0 mm | 0 cm | |
| Sept. 18 | Thundery outbreaks possible | 12° /0° | 6.2 mm | 0 cm | |
| Sept. 19 | Moderate or heavy rain with thunder | 10° /3° | 32.7 mm | 0 cm | |
| Sept. 20 | Thundery outbreaks possible | 15° /2° | 0 mm | 0 cm | |
| Sept. 21 | Cloudy | 17° /5° | 0 mm | 0 cm | |
| Sept. 22 | Partly cloudy | 18° /4° | 0 mm | 0 cm | |
| Sept. 23 | Sunny | 19° /6° | 0 mm | 0 cm | |
| Sept. 24 | Sunny | 20° /6° | 0 mm | 0 cm | |
| Sept. 25 | Sunny | 19° /7° | 0 mm | 0 cm | |
| Sept. 26 | Sunny | 21° /5° | 0 mm | 0 cm | |
| Sept. 27 | Sunny | 22° /7° | 0 mm | 0 cm | |
| Sept. 28 | Sunny | 22° /8° | 0 mm | 0 cm | |
| Sept. 29 | Sunny | 21° /9° | 0 mm | 0 cm | |
| Sept. 30 | Cloudy | 19° /7° | 0 mm | 0 cm | |
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Important Notice
Our weather forecast for Mono County 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 Mono County forecast closer to your planned date for the most up-to-date weather information.
Mono County in September - FAQ
What are the expected maximum and minimum temperatures in Mono County during September?
Enjoy moderate daytime temperatures of up to 20° and cooler nights around 6°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Mono County during September?
In September, Mono County can expect light to moderate rainfall, totaling 39.8 mm across approximately 2 days. Occasional showers are possible, and planning ahead for them could be helpful.
Will it snow in Mono County in September 2025?
Mono County typically sees 0.3 cm of snowfall during September.
What are the typical wind conditions in Mono County during September?
The average wind speed in Mono County during September is 18 km/h, suggesting breezy to windy conditions, depending on your activities.
Mono County snow forecast September 2025
Track daily snowfall levels and discover Mono County’s snowy potential this September ❄️
September rainfall patterns in Mono County
Explore the daily rainfall trends and prepare for Mono Countys September weather 💧
UV exposure in Mono County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Mono County?Get accurate weather forecasts for Mono County, located at latitude 37.649 and longitude -118.972. Stay updated with localized weather information tailored for Mono County.
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