Hanoi has a mild, tropical climate typical of northern Vietnam with a dry season from November to April and a wet season from May to October. The months of June through August are typically the hottest and wettest.
Best Time to Come
The best time to come to Hanoi is from September to November or from March to April, when the weather is mild. Temperatures during these months range from 18°C to 30°C and the days stay relatively dry. From November to March, there is less rain but it can get quite cold in the evening so bring a warm jacket if visiting during this time. Most homes in Hanoi do not have heating so be sure that there are extra blankets on hand for a comfortable sleep.
Hanoi has two main seasons, the northeast monsoon months of November to April and the southwest monsoon months of May to October. The northeast monsoon season can be further divided into a winter season from November to February, which sees the coolest and driest days with average temperatures of 10-15°C and only 20mm of rain. Springtime runs from February to April, when warmer temperatures are accompanied by more rain, up to 80mm in April. The southwest monsoon summer months of May to September can get uncomfortably hot (temperatures into the mid-30s) and humid with heavy rains, especially in July and August when each month gets an average 320mm of rain. The autumn months of September to November are generally sunny and mild.
Being inland, Hanoi escapes the brunt of the summer typhoon storms, but there can be some wild weather to watch out for.