The annual monsoon cycles that affect all of mainland Southeast Asia produce a dry and wet monsoon climate with three basic seasons for most of Laos. The southwest monsoon arrives between May and July and lasts until November. The rainy season is not as bad as you might think. It will rain heavily but the downpours are usually brief and can be followed by long periods of sunshine. The good thing about the rain is that is clears dust from the skies and land, which makes everything a lot clearer and brighter.