WEATHER CONDITIONS IN BOLIVIA AND REGIONAL VARIATIONS
According to the different climatic characteristics in our territory and taking into account the spatial and temporal distribution of rainfall and temperature, latitudinal and altitudinal factors allowed us to regionalize the country into four zones that follow the same climate regime: Altiplano, Valles , Llanos Orientales (Beni, Pando, north of La Paz and Santa Cruz mountains except the province) and Tierras Bajas.
WEATHER PATTERNS BY REGION
The following description is made on the basis of our national network of meteorological stations and our database.
In the Altiplano rainfall varies from 1200 mm (1 mm = 1 liter of water per square meter) near Lake Titicaca to 200 mm on the salt flats. The climate of this area is a function of its altitude, of 3800 meters. Some characteristics of this area are the presence of frost almost all year with the highest incidence recorded in June and July (winter season). The average temperature is 10 º C.
It is important to note that around Lake Titicaca, we see a characteristic microclimate by the presence of higher percentage of moisture in the area because of the Lake's thermoregulatory action which is reflected in the increase in average temperatures close to the 15 º C.
The Valley region is characterized by a temperature between 10 ° C to 20 º C, considering an average value of 18 º C, in regard to precipitation it ranges between 600 mm to 700 mm.
The tropical valleys of La Paz and Cochabamba have different behavior in the maximum temperatures exceeding 30 º C and as for rainfall this is above 3000 mm, as is the case of Chapare which is the region with higher volumes of precipitation in the country, with over 5000 mm per year.
In the Llanos Orientales (eastern plains) annual rainfall amounts reach between 1800 to 2000 mm. The average temperature is 25 º C and can drop abruptly when the cold fronts come, also known as surazos.
The rainfall in the Chaco region or Lowland varies in intensity from north to south, the range is 1200 to 700 mm annually. The average temperature is 23 º C, but there are steep declines over the entry of cold fronts from the south, they are known as surazos.
This region is characterized by a deficit in terms of precipitation, where droughts are frequent and very high maximum temperatures, as is the case of Villamontes, in spring and summer above 40 º C.
It is noteworthy that in our country the rainy season begins in November and runs until March, if conditions are normal with highs in the months of December and January, this period coincides with the austral summer, while the winter season is characterized by little or almost no rainfall in the west of our country and on the east a lot depends on the income of cold fronts from the far south of our continent, which coincides with winter in the Southern Hemisphere. The other months are considered transtional.