When it comes to weather, it's a tough call, as Vietnam's climate is so diverse. Think frosts and occasional snow in the mountains of the north, and temperatures soaring to 40?C in the south during the dry season. Vietnam's weather is dictated by two monsoons. The winter monsoon comes from the northeast between October and March, bringing damp and chilly winters to all areas north of Nha Trang, and dry and warm temperatures to the south. From April or May to October, the summer monsoon brings hot, humid weather to the whole country except for those areas sheltered by mountains. For the best balance, try the months of April, May or October. For those sticking to the south, November to February is dry and a touch cooler. From July to November, violent and unpredictable typhoons hit centrel and northern Vietnam, which can dampen the spirits of even the most enthusiastic traveler. It gets pretty crowded from November to March and in July and August. Prices tend to peak over the Christmas and New Year period, and if you don't fancy sharing the sites with the masses, try to avoid these busy times. Some travelers like to time a visit with Test (Vietnamese New Year), which is the biggest festival in the calendar in late January or early February;a nice idea, but not ideal, as the whole country is on the move. High season in Vietnam runs from November to March, with a summer surge in July and August, particularly for domestic tourists. May, June and September are usually the quietest months.