Houston Weather in September
United States · Humid Subtropical climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
September in Houston sees average temperatures ranging from a low of 22.5°C (72.5°F) to a high of 31.3°C (88.3°F), with a mean of 26.4°C (79.5°F). Compared to the annual average of 21.3°C (70.3°F), this month is 5.1°C warmer than the yearly norm. Precipitation averages 150.0mm, making it approximately 12.0mm drier than the monthly average of 162.0mm. The city receives an average of 10.0 hours of sunshine per day during September, with relative humidity averaging 74.7%. Wind speeds reach an average maximum of 17.2 km/h. For travelers, this month offers a temperature experience in Houston, with drier-than-average conditions compared to the rest of the year.
If you're planning outdoor activities in Houston, accept that humidity is the third dimension of every weather reading. I ran Buffalo Bayou Park in May at 7am: 24°C but 90% humidity, like jogging through warm soup. June-September is genuinely oppressive — 34°C with 75% humidity, heat index pushing 40°C. Best outdoor windows: March-April and October-November, 22-26°C with manageable humidity. Hurricane season (August-September) can disrupt everything. Winter is mild but unpredictable — I once did a January bike ride in 25°C, then a February one in 5°C. Always check radar; Gulf storms intensify fast.
September vs Adjacent Months
| Metric | August | September | October |
|---|---|---|---|
| Mean Temp | 28.9°C (84.0°F) | 26.4°C (79.5°F) | 22.3°C (72.1°F) |
| Rainfall | 125.6mm | 150.0mm | 122.9mm |
| Sunshine | 11.0 hrs | 10.0 hrs | 9.3 hrs |
| Humidity | 75.2% | 74.7% | 70.7% |
| Wind | 17.6 km/h | 17.2 km/h | 19.3 km/h |
| Rainy Days | 19.4 | 17.2 | 12.4 |
Seasonal Context
September falls in Autumn in the Northern Hemisphere. Autumn sees temperatures gradually cooling from summer highs. For travelers visiting Houston 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 Houston in September?
The average temperature in Houston during September ranges from 22.5°C (72.5°F) to 31.3°C (88.3°F), with a mean of 26.4°C (79.5°F).
How much does it rain in Houston in September?
Houston receives an average of 150.0mm of precipitation in September, spread across approximately 17.2 rainy days.
What should I pack for Houston in September?
Based on September weather data, pack lightweight, breathable clothing, sunscreen, and a hat. Rain gear is essential — this month averages 150.0mm of precipitation.
Is September a good time to visit Houston?
September is a month with challenging conditions. Plan activities carefully and stay hydrated.
Other Months for Houston
Cities with Similar September Climate (Humid Subtropical)
Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: 29.76°, -95.37°. Timezone: America/Chicago. Last updated: 2026-07-30.