September in Rowlett averages a daily high of 31.7°C with nights around 18.1°C. Expect roughly 6 wet days totalling 69.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Rowlett is March–April.
Based on LAVON DAM, TX US (16.4km), 1995–2024. 18 years of September data.