Winters in Bayonne are quite chilly, with temperatures often dropping below freezing and averaging around 2-6 degrees Celsius. Spring brings a gradual warming trend, with temperatures rising to an average of 12 degrees Celsius by April. Summer is mild and pleasant, with highs reaching up to 35-36 degrees Celsius from July to August, but also experiencing some warm days in May and June. Autumn is similar to spring, with temperatures gradually cooling down after the warmth of summer, averaging around 17 degrees Celsius in October. Overall, Bayonne's temperature fluctuations are relatively moderate throughout the year, with cold winters and pleasant summers.