Winters in Bollate are chilly, with temperatures often dropping below freezing and averaging around 2-6°C. Spring brings a slow warming trend, with temperatures gradually rising to averages of 8-14°C by May. Summers are mild, with highs rarely exceeding 33°C and overnight lows ranging from 5-7°C. Autumn is similar to spring in terms of temperature fluctuations, with averages dropping back down to around 7-11°C by October.