Winters in Numazu are harsh, with temperatures often plummeting below -30°C, making it one of the coldest seasons. Spring brings a gradual warming trend, with temperatures rising steadily from around 8°C in March to an average high of 14°C in May. Summer is hot and humid, with temperatures frequently reaching above 30°C, especially in July and August. Autumn is mild, with September being the warmest month before the temperature drops again in October.