The tropical south
The difference in precipitation between the two seasons (dry from November to May and rainy from June to October) is more obvious than elsewhere in Vietnam. However, the rain in the wet season is often limited to heavy showers at the end of the afternoon, and the weather is warm throughout the year. Annual rainfall in the south is approximately 80 inches (2,000 millimetres) while temperatures remain relatively constant – on average between 25°C and 35°C (77°F-95°F).

The Mekong
The climate in the Mekong Delta is sub-equatorial with two main seasons. The wet season lasts from May to October with short downpours occurring almost every day. The dry season lasts from November to April with the last three months of this period being very hot and humid. However, the rainfall is far from continuous: it is only at the peak of the summer that heavy downpours and tropical storms are frequent.

There is no obvious time to visit the Mekong Delta time. For those who want to avoid excessive heat, the rainy season would be a better choice. The air is cooler and it is not as dusty as in the dry season. However, if you do choose this season, it would be best to go at the beginning because the Delta, an area of very low relief, often suffers from flooding caused by the massive volume of water from heavy rainfall in the mountains of Cambodia, Thailand and Laos. In 1992, flooding was severe. Over 180 people died, a million people were displaced, and a large percentage of the rice harvest was wiped out. At times of flooding, sanitation can also be a problem.

Flooding is a phenomenon that affects local people. Over the years, they have modified their dwellings and farming patterns to cope with the flooding, but there is obviously an increased risk of drowning, with children particularly at risk. Visitors travel along raised roads and by boat. For them, the floods are an opportunity to witness the way in which people have adapted to the three months when much of the delta can be as much as three metres underwater.