When to visit North Vietnam (Sapa, Hanoi, Halong Bay):
You are most likely to experience warm and sunny days during the months of March, April and September to November.
When to visit Central Vietnam (Hue, Hoi An):
You can best enjoy your experience in Central Vietnam between the months of February and August.
When to visit South Vietnam (Ho Chi Minh City, Mekong Delta):
Temperatures may reach 40-degree Celsius from March to May. Otherwise, it is suitable to visit year-round.