The average temperature in Hanoi is 15 to 20 degrees in the winter and 30 to 35 degrees in the summer.
The climate in Vietnam varies greatly from north to south. Tropical monsoons occur from May to October in the north and south and from September to January in the centre. It is almost totally dry throughout the rest of the year.
Loose, natural fabrics all year, but warmer clothing is required in the highlands, and in the winter in North Vietnam. Rainwear is essential during the wet season.