Somerville experiences a relatively cold winter, with temperatures often below freezing, averaging around -2°C in January and February. As spring approaches, temperatures gradually warm up, reaching an average of 9°C in April and 15°C in May. Summer is mild to warm, with temperatures ranging from 13°C to 35°C, peaking in July and August at an average of 21-23°C. Autumn brings a cooldown, with temperatures returning to around 6-14°C by November and December, marking the onset of another chilly winter.