July in Blackburn averages a daily high of 20.4°C with nights around 12.5°C. Expect roughly 15.4 wet days totalling 94.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Blackburn is May–September.
Based on PRESTON MOOR PARK, UK (14.7km), 1995–2024. 24 years of July data.