September in Meridian averages a daily high of 26.9°C with nights around 11.6°C. Expect roughly 4.1 wet days totalling 11.3mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Meridian is June.
Based on BOISE AIR TERMINAL, ID US (13.2km), 1995–2024. 30 years of September data.