When to Go
Around Halong Bay, the season runs from early summer to mid-autumn. From July to September beware of tropical typhoons; flooding in Haiphong and Hanoi is common during these storms. The capital is hot and extremely humid in summer, which makes it a popular time for residents to head for the hills or the coast.
During Tet, the lunar new year, you'll find northern Vietnam cold and drizzly but extremely festive. If you're coming during this time, make flight and hotel reservations very early. Also understand that many tour operations, such as trips to Halong Bay, are limited or suspended during this period.