Despite having two distinct weather seasons you can travel in Laos all-year-round and with no coastline to influence things, Laos’ weather system is relatively straight-forward compared with much of Asia; consisting of a dry season (October to late April) and a wet season (May to late September). Within each season there are variations in temperature, with the dry months leading up to the wet season (March and April) and the early wet season (May and June) typically being the hottest of the year.
Temperatures throughout the country are also greatly affected by altitude with much of the country at a level that reduces the country’s average temperatures by several °C. As a general rule north, central and eastern regions are at a higher altitude than those in the south, where at its lowest, in the Mekong River valley, humidity is higher and temperatures in excess of 35°C are not uncommon between March and April.
The early months of the wet season (May to July) remain very hot and rainfall is often short lived, whilst in the latter months (late July until September) the rains become more constant and can be heavy at times, especially in southern parts of the country.
Further north and in Luang Prabang, rainfall tends to be lighter and you can often expect rain during the night or mornings with some relatively clear afternoons. Across Laos, throughout much of the rainy season, daytime temperatures average around 29°C in the lowlands and 23°C in the mountain valleys.
Throughout the country in all but the hottest months of the year it is often advisable to have a jumper or fleece for the evenings, when there is a tendency for it to get quite cool.