Vientiane sits in the Mekong River valley in central Laos, where the wet season from May through October brings the bulk of the year’s rainfall and the Mekong’s seasonal rise is the region’s primary flood driver.
Laos’s capital sits directly on the Mekong River, whose seasonal rise during the wet season is the city’s primary flood risk. Because Laos sits far upstream in the Mekong basin, a wet monsoon season here can also signal what’s coming for countries further downstream, and Laos’s Department of Meteorology and Hydrology uses radar alongside river gauges to track both direct rainfall and the river’s slower seasonal rise. Learn more: Flash Flood Warning Signs on Radar · Open the full Rain Map