September in Ishim averages a daily high of 15.8°C with nights around 5.4°C. Expect roughly 12 wet days totalling 42.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Ishim is May–August.
Based on ISCHIM AMSG, RS (3.8km), 1995–2024. 25 years of September data.