When to Go
In terms of weather, the ideal time to visit Hanoi is between October (with temperatures averaging 80 degrees Fahrenheit) and mid-December (with temperatures ranging from the upper 60s to mid-70s), when the heat and humidity are not so oppressive. But be prepared for cold snaps and chilly nights. The brief spring from March to April is also a pleasant time. From January to March a layer of clammy mist—the infamous mua phun—hovers over Hanoi. The city begins its summer swelter in May and sweats through August, when the monsoons bring heavy downpours and sudden flooding. This continues until late September, so if you choose to brave the elements at this time, bring rubber footwear and rain pants or buy them in Hanoi because you could be in it up to your knees. Temperatures range from the mid-70s to the high 90s.
Festivals and Events
Tet. Late January to early February is a good time to visit if you want to breathe in the excitement of Tet, the lunar new year, a movable date based on the Chinese lunar calendar. In preparation for Vietnam's largest festival, the Old Quarter comes alive with floor-to-ceiling displays of moon cakes, red banners, joss sticks, and red envelopes for giving lucky money (mung tuoi) to children. Beware: when Tet does arrive, many shops and restaurants close for up to a week—although some restaurants have discovered the financial benefits of staying open. If you're planning to conduct any business, this is definitely not the time to do it. Hanoi, Ha Noi.
Pilgrimage to the Perfume Pagoda. February and March are the months to join the mass Buddhist pilgrimage to the Perfume Pagoda, but be prepared to deal with serious crowds—many thousands each day—if you make the trip during this peak season. Smaller religious festivals take place at Hanoi's temples and outlying villages in March and April. Because all Vietnamese festivals follow the lunar calendar, check online or with your tour operator for exact dates. Hanoi, Ha Noi.