Last updated: June 24, 2025
In Vista Santa Rosa, United States, the average temperature in September hovers around 28°C (83°F), with extremes ranging from a cool 11°C (51°F) to a scorching 45°C (114°F). The month experiences minimal rain, with just 4 mm (0.2 in) of precipitation over a single day, and the air maintains a comfortable average humidity level of 52%.
In September in Vista Santa Rosa, the average temperature is 28°C (83°F), with maximums reaching up to 45°C (114°F) and minimums dropping as low as 11°C (51°F). Be prepared for a diverse range of temperatures, making it essential to pack accordingly for your travels.
In Vista Santa Rosa in September, the precipitation amount is 4 mm (0.2 in) during 1 day.
In Vista Santa Rosa in September humidity is 52%. With an average temperature of 28°C (83°F), this humidity feels like a warm embrace, making travel enjoyable yet slightly sticky, so staying hydrated and taking breaks in shaded areas is essential.
In Vista Santa Rosa in September, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Vista Santa Rosa.
UV Risk Categories
Weather in Vista Santa Rosa varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Vista Santa Rosa, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 12°C (53°F) | 28 mm (1.1 inches) | 72% | moderate |
| February Weather | 13°C (55°F) | 28 mm (1.1 inches) | 77% | high |
| March Weather | 15°C (60°F) | 18 mm (0.7 inches) | 67% | very high |
| April Weather | 20°C (68°F) | 11 mm (0.4 inches) | 56% | extreme |
| May Weather | 23°C (73°F) | 2 mm (0.1 inches) | 46% | extreme |
| June Weather | 29°C (84°F) | 1 mm (0.0 inches) | 48% | extreme |
| July Weather | 32°C (89°F) | 10 mm (0.4 inches) | 46% | extreme |
| August Weather | 32°C (89°F) | 7 mm (0.3 inches) | 42% | extreme |
| September Weather | 28°C (83°F) | 4 mm (0.2 inches) | 52% | extreme |
| October Weather | 21°C (71°F) | 6 mm (0.2 inches) | 58% | very high |
| November Weather | 16°C (61°F) | 10 mm (0.4 inches) | 66% | moderate |
| December Weather | 11°C (52°F) | 27 mm (1.1 inches) | 74% | moderate |