Phoenix Weather in September
United States · Hot Desert climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
September in Phoenix sees average temperatures ranging from a low of 24.9°C (76.8°F) to a high of 38.3°C (100.9°F), with a mean of 31.8°C (89.2°F). Compared to the annual average of 23.8°C (74.8°F), this month is 8.0°C warmer than the yearly norm. Precipitation averages 18.3mm, making it approximately 6.0mm drier than the monthly average of 24.0mm. The city receives an average of 11.4 hours of sunshine per day during September, with relative humidity averaging 30.4%. Wind speeds reach an average maximum of 19.0 km/h. For travelers, this month offers a temperature experience in Phoenix, with drier-than-average conditions compared to the rest of the year.
Phoenix's hot desert climate is one of the most extreme in the United States. I've studied the summer data and found that temperatures regularly exceed 40°C from June to August. The best time for visiting is November to March, when daytime temperatures are pleasant and the city's outdoor attractions are accessible. The winter months are mild and sunny, making Phoenix a popular winter destination.
September vs Adjacent Months
| Metric | August | September | October |
|---|---|---|---|
| Mean Temp | 34.4°C (93.9°F) | 31.8°C (89.2°F) | 25.3°C (77.5°F) |
| Rainfall | 45.2mm | 18.3mm | 9.7mm |
| Sunshine | 12.0 hrs | 11.4 hrs | 10.6 hrs |
| Humidity | 36.2% | 30.4% | 27.5% |
| Wind | 20.0 km/h | 19.0 km/h | 16.5 km/h |
| Rainy Days | 7.4 | 3.6 | 2.2 |
Seasonal Context
September falls in Autumn in the Northern Hemisphere. Autumn sees temperatures gradually cooling from summer highs. For travelers visiting Phoenix in September, the data indicates mixed conditions based on the combination of temperature, precipitation, and daylight hours.
Frequently Asked Questions
What is the average temperature in Phoenix in September?
The average temperature in Phoenix during September ranges from 24.9°C (76.8°F) to 38.3°C (100.9°F), with a mean of 31.8°C (89.2°F).
How much does it rain in Phoenix in September?
Phoenix receives an average of 18.3mm of precipitation in September, spread across approximately 3.6 rainy days.
What should I pack for Phoenix in September?
Based on September weather data, pack lightweight, breathable clothing, sunscreen, and a hat.
Is September a good time to visit Phoenix?
September is a month with challenging conditions. Plan activities carefully and stay hydrated.
Other Months for Phoenix
Cities with Similar September Climate (Hot Desert)
Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: 33.45°, -112.07°. Timezone: America/Phoenix. Last updated: 2026-07-30.