Bolivia’s climate varies widely between eco-regions, from tropical conditions on the eastern plains to a polar climate in the western Andes.
Summers are hot, humid in the east and dry in the west with rains that modify temperature, humidity, wind, atmospheric pressure, and evaporation, giving rise to different climates. When the climatic and erratically cyclical phenomenon called El Niño occurs, it generates great alterations in the climate. Another phenomenon is the so-called “Surazo” because it is a glacial wind that travels the continent from north to south from the Antarctic region, the temperature decreasing notably in most of the territory, it happens from winter to September three times a year for short periods and lasts some days.
Winters in the west are fairly cold and present snow in the vicinity of the mountains, while the lowlands tend to have windy days. Autumn is dry in non-tropical regions. Climatic variations by regions occur as follows:
Llanos
Tropical humid climate with average temperature of 30 ° C. Winds from the Amazon forest cause significant rainfall. From May, dry winds produce a minimum precipitation so the days are cleared. The Surazo, brings cold temperatures for several days.
High Plateau
Arid-polar climate swept by strong glacial winds. The average temperature is between 10 and 20 ° C during the day according to the high plateau, and at night the temperatures fall drastically between 0 ° C and (-) 20 ° C below zero. The climate is dry and the solar radiation is intense. Frost occurs almost every month and snow is frequent.
Valleys and Yungas
The weather is warm. Northeastern wet winds are pushed into the mountains, making this area wet and rainy. The temperatures fall with the increase of the height, nevertheless the snows are possible in elevations that oscillate the 2500 masl.
Chaco
Semi-tropical, semi-arid climate. It shows rain and humidity during January, rest of months are dry with hot days and cool nights. The maximum temperature recorded in Bolivia was 47 ° C and occurred in this area. The surazos also affect this region.
