Laos enjoys a tropical climate with two distinct seasons - the rainy season from the beginning of May to the end of September and dry season from October through to April. The yearly average temperature is about 28 C, rising to a maximum of 38 C in April and May. In Vientiane minimum temperatures of 19 C are to be expected in January. In mountainous areas, however, temperatures drop to 14-15 C during the winter months, and in cold nights easily reach the freezing point.
The average precipitation is highest in southern Laos, where the Annamite mountains receive over 3000 mm annually. In Vientiane rainfall is about 1500-2000 mm, and in the northern provinces only 1000-1500 mm.
FLORA AND FAUNA
Laos has one of the most pristine Ecologies in South East Asia. An estimated half of its woodlands consist of primary forest, in particular the tropical rain forest. Unlike the vegetation in the bored climate of northern Europe and the United States, tropical rain forest is composed of three vegetative layers. The top layer is dominated by single-trunked, high-reaching trees, so-called dipterocarps. The middle canopy consists of hardwood such as teak. Beneath, small trees, grasses, and sometimes bamboo can be found.
In addition to a fascinating vegetation, Laos plays host to a diverse animal kingdom. Several exotic mammals are endemic such as leopard cats, Javan mongoose, goat-antelopes, rare species of gibbons and langurs, Malayan sun bear. Asiatic black bear, gaur and others. The discovery of the Saola Ox, a breed of deer-antelope, in Vietnam a few years ago caused a sensation. This extremely rare animal inhabits the eastern border regions of Laos, too. And these remote areas probably still hide other unknown species.
In the south of Laos, near Khong Island, Irrawaddy dolphins inhabit the Mekong river. While many species of wildlife are shy and can rarely be seen, spectators will generally be able to spot the dolphins in spring when the water level of the Mekong is lowest. Laos is also rich in resident and migrating birds. One of the more notable ones is the rare Green Peafowl.
Lao language is the national language. Other languages used are French, English, Chinese, Thai and Vietnamese.