Semarang is hot and humid year-round, with temperatures hovering around 30°C. The city sits on the north Java coast and has a tropical monsoon climate. The dry season runs from May to October and is the better time to visit — the days are clearer and the streets less flooded. The rainy season (November to April) brings heavy afternoon downpours that can make walking uncomfortable and occasionally flood the lower parts of the city, particularly around the historic district.
The Lunar New Year celebrations at Sam Po Kong temple and in the Chinese quarter of Pecinan are spectacular and worth timing a visit around. The exact dates shift each year with the lunar calendar.