There are no good or bad seasons for a visit to Vietnam. Depending on the region chosen, travelers may not have to worry too much about variations in weather. In Ho Chi Minh City, for example, temperatures are fairly constant throughout the year, though rainfall is most concentrated from May through October. In Hanoi, however, winters are gray and dry, while summers are very hot and humid with heavy rain. During Tet, Vietnam's New Year celebration in late January or early February, flights and hotels can be difficult if not impossible (or horrendously expensive) to find.