Most public holidays in Vietnam are to honor important historical events or to celebrate cultural values among Vietnamese. Some holidays vary from year to year due to the time difference between the lunar and solar calendar.
Vietnamese people follow the standard 12-month calendar in daily life. Most village festivals and holidays in Vietnam follow the traditional Chinese calendar, which counts 355 days and adds a “leap month” every three years to keep track of the sun calendar. Following the Chinese lunar calendar means that most holidays correspond to the full moon. This also means that holidays fall on different calendar dates every year.
Winter temperatures can be bitterly cold in the far north, with even snow possible. The further south you go, the milder the weather. Tet parties take place at the end of the month (or in February).