Last updated: June 24, 2025
In San Tan Valley, United States, the average temperature in September is a warm 30°C (87°F). However, don't be surprised by the temperature fluctuations: it can drop to a cool 12°C (55°F) at its lowest and soar to a scorching 44°C (111°F) at its peak. During the month, you can expect 29 mm (1.2 in) of precipitation spread over approximately 3 days, while the average humidity rests at a comfortable 64%.
In September, in San Tan Valley, the average temperature is 30°C (87°F). The maximum can reach 44°C (111°F), and the minimum can be as low as 12°C (55°F). Travelers should be prepared for a wide range of temperatures, ensuring they pack accordingly for both heat and cooler evenings.
In San Tan Valley in September, the total precipitation amount is 29 mm (1.2 in) over a duration of 3 days.
In San Tan Valley in September humidity is 64%. With an average temperature of 30°C (87°F), this humidity feels like a warm, muggy embrace, making travel a bit sticky and uncomfortable but also inviting you to slow down and savor refreshing breaks in the shade.
In San Tan Valley in September, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in San Tan Valley.
UV Risk Categories
Weather in San Tan Valley varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in San Tan Valley, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 12°C (54°F) | 33 mm (1.3 inches) | 76% | moderate |
| February Weather | 13°C (56°F) | 42 mm (1.7 inches) | 79% | high |
| March Weather | 17°C (64°F) | 25 mm (1.0 inches) | 67% | very high |
| April Weather | 23°C (73°F) | 2 mm (0.1 inches) | 55% | extreme |
| May Weather | 27°C (80°F) | 3 mm (0.1 inches) | 40% | extreme |
| June Weather | 33°C (91°F) | 3 mm (0.1 inches) | 33% | extreme |
| July Weather | 34°C (93°F) | 45 mm (1.8 inches) | 34% | extreme |
| August Weather | 33°C (92°F) | 34 mm (1.4 inches) | 48% | extreme |
| September Weather | 30°C (87°F) | 29 mm (1.2 inches) | 64% | very high |
| October Weather | 24°C (75°F) | 20 mm (0.8 inches) | 67% | very high |
| November Weather | 18°C (65°F) | 21 mm (0.8 inches) | 77% | moderate |
| December Weather | 12°C (55°F) | 30 mm (1.2 inches) | 82% | moderate |