June in Saint John averages a daily high of 17.5°C with nights around 9.2°C. Expect roughly 12.8 wet days totalling 108.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Saint John is July–September.
Based on POINT LEPREAU CS, NB CA (38.3km), 1995–2024. 28 years of June data.