Although Bolivia lies entirely within tropical latitudes, climatic conditions vary widely from tropical in the lowlands to polar in the highest parts of the Andes. Temperatures depend primarily on elevation and show little seasonal variation. In most locations, rainfall is heaviest during the Southern Hemisphere summer, and yearly amounts tend to decrease from north to south. This means that summers are hot and wet and winters cold and dry.

Northern lowland areas have a tropical wet climate with year-round high temperatures, high humidity, and heavy rainfall. Daytime highs average more than 30° C all year in most locations. The rain-bearing northeast trade winds, blowing across the Amazon Basin, bring significant rainfall amounts. Rain often falls in brief thunderstorms, sometimes accompanied by strong winds and hail.

Central lowland areas have a tropical wet and dry climate. From October through April, northeast trade winds predominate, and the weather is hot, humid, and rainy. From May through September, however, dry southeast trade winds take control, and precipitation is minimal. During this season, clear days and cloudless nights allow for higher daily maximums and lower nightly minimums than occur during the rainy season. Occasional incursions of strong winds from the south, called surazos, can reach this region during winter and bring cool temperatures for several days.