Mariposa County (Yosemite National Park)
September
Weather in Mariposa County, California for September 2026
Your guide to Mariposa County weather in September - trends and predictions
Snowfall in Mariposa County during September is quite rare, with fewer than 2 snowy days on average.
In general, the average temperature in Mariposa County at the beginning of September is 21.9 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 17.7 °F by the end of September.
With an average of 2 rainy days, Mariposa County experiences minimal rainfall in September.
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Snow Forecast ❄️
Temperatures
Rain 🌧️
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27
Dry days
2
Rainy days
1
Snow days
19°/9°
Temperatures
20 km/h
Avg max wind
37 %
Avg humidity
Mariposa County Weather September
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Temperatures trend during September in Mariposa County
See the weather trend as well as the moving average line
September weather in Mariposa County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 23° /13° | 0 mm | 6 | |
| Sept. 2 | Sunny | 21° /12° | 0 mm | 6 | |
| Sept. 3 | Sunny | 21° /11° | 0 mm | 6 | |
| Sept. 4 | Sunny | 22° /12° | 0 mm | 6 | |
| Sept. 5 |  Patchy rain possible | 23° /13° | 0.1 mm | 6 | |
| Sept. 6 |  Partly cloudy | 22° /12° | 0 mm | 6 | |
| Sept. 7 | Sunny | 21° /11° | 0 mm | 6 | |
| Sept. 8 | Sunny | 20° /10° | 0 mm | 6 | |
| Sept. 9 | Sunny | 16° /8° | 0 mm | 4 | |
| Sept. 10 |  Overcast | 14° /6° | 0 mm | 4 | |
| Sept. 11 | Sunny | 14° /4° | 0 mm | 4 | |
| Sept. 12 | Sunny | 16° /5° | 12.1 mm | 4 | |
| Sept. 13 | Sunny | 18° /7° | 0 mm | 6 | |
| Sept. 14 |  Cloudy | 19° /8° | 0 mm | 5 | |
| Sept. 15 | Sunny | 18° /7° | 0 mm | 5 | |
| Sept. 16 |  Patchy light snow with thunder | 13° /6° | 1.2 mm | 4 | |
| Sept. 17 | Cloudy | 15° /7° | 0 mm | 4 | |
| Sept. 18 |  Thundery outbreaks possible | 12° /8° | 2.3 mm | 3 | |
| Sept. 19 |  Moderate or heavy rain shower | 10° /6° | 13.5 mm | 3 | |
| Sept. 20 | Sunny | 16° /7° | 0 mm | 5 | |
| Sept. 21 | Sunny | 16° /9° | 0 mm | 5 | |
| Sept. 22 | Partly cloudy | 19° /10° | 0 mm | 5 | |
| Sept. 23 | Sunny | 20° /11° | 0 mm | 5 | |
| Sept. 24 | Partly cloudy | 19° /11° | 0 mm | 5 | |
| Sept. 25 | Sunny | 17° /11° | 11.4 mm | 4 | |
| Sept. 26 | Sunny | 19° /10° | 0 mm | 6 | |
| Sept. 27 | Sunny | 19° /11° | 2 mm | 5 | |
| Sept. 28 | Sunny | 17° /11° | 0 mm | 5 | |
| Sept. 29 | Sunny | 17° /9° | 0 mm | 5 | |
| Sept. 30 | Cloudy | 16° /9° | 0 mm | 4 | |
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Important Notice
Our weather forecast for Mariposa 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 Mariposa County forecast closer to your planned date for the most up-to-date weather information.
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Mariposa County in September - FAQ
What are the expected maximum and minimum temperatures in Mariposa County during September?
Enjoy moderate daytime temperatures of up to 19° and cooler nights around 9°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Mariposa County during September?
In September, Mariposa County can expect light to moderate rainfall, totaling 21.7 mm across approximately 2 days. Occasional showers are possible, and planning ahead for them could be helpful.
Will it snow in Mariposa County in September 2026?
Mariposa County typically sees 0.93 cm of snowfall during September.
What are the typical wind conditions in Mariposa County during September?
The average wind speed in Mariposa County during September is 20 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Mariposa County
Explore the daily rainfall trends and prepare for Mariposa Countys September weather 💧
Typically, Mariposa County has 2 rainy days in September with a total of 21.7 mm of rainfall.
UV exposure in Mariposa County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Mariposa County?Get accurate weather forecasts for Mariposa County, located at latitude 37.848 and longitude -119.557. Stay updated with localized weather information tailored for Mariposa County.
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