Hanoi is situated in a tropical monsoon zone with two main seasons. During the dry season, which lasts from October to April, it is cold and there is very little rainfall, except from January to March, when the weather is still cold but there is some light rain.

The wet season, from May to September, is hot with heavy rains and storms. The average annual temperature is 23.2ºC (73.7ºF) and the average annual rainfall is 1,800mm.

The average temperature in winter is 17.2ºC (62.9ºF), but can go down to 8ºC (46.4ºF). The average temperature in summer is 29.2ºC (84.6ºF), but can reach up to 39ºC (102.2ºF).