July in Biysk averages a daily high of 26.5°C with nights around 13.9°C. Expect roughly 12.9 wet days totalling 67.4mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Biysk is May–September.
Based on BIJSK ZONALNAJA, RS (23.2km), 1995–2024. 30 years of July data.