Iruma, Japan experiences a temperate climate with distinct seasonal variations. Winters are quite chilly, with temperatures ranging from around -7°C to 18°C on average in January and December, bringing frosty mornings and occasional warm days. As spring approaches, temperatures gradually rise, reaching averages of 14°C in April and 19°C in May, with mild conditions prevailing during this time. Summers are hot and humid, with July and August often seeing temperatures soar above 30°C, while autumns bring a welcome cooling trend, returning to more moderate temperatures by October.