Katsushika-ku's winters are chilly and unpredictable, with temperatures often dropping below freezing in January and December. Spring brings mild temperatures, gradually warming up to average highs around 14°C by April. Summer is hot and humid, with July and August being the warmest months, but temperatures can drop significantly at night. Autumn sees a return to more moderate weather, with October's temperatures mirroring those of March, before cooling down again in November.