Laos has three distinct seasons. The hot season is from Mar-May, when temperatures can soar as high as 40°C and the humidity makes it feel like 50°C. The slightly cooler wet season is from May-Oct, when temperatures are around 30°C, tropical downpours are frequent (especially Jul-Aug), and some years the Mekong floods.
The dry season from Nov-Mar, which has low rainfall and temperatures as low as 15°C (or even to zero in the mountains at night), is “high season”. However, towards the end of the dry season, the northern parts of Laos — basically everything north of Luang Prabang — can become very hazy due to farmers burning fields and fires in the forests.
Being in transit by air, road or river in Laos can be as rewarding as the destination itself – but allow plenty of leeway in your schedule for the near-inevitable delays, cancellations and breakdowns.
Vientiane International Airport. Luang Prabang International Airport. A good source of bus timetables, including some basic town maps, can be found at hobomaps.com.