Laos can be visited throughout the year. However, those planning to travel extensively by road in the northern part of the country and/or south of the Boloven Plateau should avoid the last two months of the rainy season when some countryside roads may be impassable.

Laos enjoys a tropical climate with three distinct seasons. The dry or cool season begins end of October and lasts until end of February (average 20-25°C). Take along a pullover or jacket during the cool season, as nights can be cold, especially in the mountainous areas such as Luang Prabang, the Plain of Jars, Saravane and Houeixai (0-5°C). The hot season lasts from March to June, light cotton clothes and hats are recommended (average 35°C). From June to early October is the rainy season (average 25-30°C). Most precipitation comes in the afternoon and in the evening. Rainfall varies considerably from area to area with the highlands in the Phou Louang range alongthe Lao / Vietnam border receiving the most precipitation (300+ mm per year). Vientiane sees an average of 150 - 200 mm per year and Luang Prabang 100 - 150 mm per year.