"Every day has four seasons," was one of the first sentences told to me by "Paceños" (people from La Paz, Bolivia).
"It rains, gets hot, then cloudy and after that it goes back to the relentless windy cold," they continued. This definition of seasons was odd and true only because I had arrived in February, one of the few rainy months on the Andean High Plateau.
I didn’t expect accuracy from people that have never left their hometown; moreover, exactitude is difficult in a city with a vertical span of over 800m, where the upper parts cross the four kilometers altitude line. The Pacific Ocean – if it could be seen from the city – would look just as a large pond; La Paz resembles a brick built space station attached to the Andes. Its extremely broken terrain assures even more climatic irregularities; one shaded steep street is constantly hit by wild winds, the next one is baked under the high altitude radiation.
Formal statistics are misleading. At their lowest, temperatures go just below freezing point. At their highest, they would be considered just as a hot winter day in my hometown. Nothing extreme on the paper; yet, reality is different. At this altitude, temperatures and winds can change abruptly. Under the sun one gets baked; a foot from there and under the shade, it can get really cold regardless the formal season.
Bolivia is too close to the equator for solar seasons make any sense. If ignoring the solar calendar then the Andean High Plateau climate patterns vaguely resemble locations in the northern hemisphere. July and August are sunny and dry while January and February are rainy. This is a very useful rule of thumb, but it is worth remembering also a few other details. From late December to March it is rainy, it can rain at all hours, but more often than not it happens during the night. In late February, the rain will turn into hailstones. In the lower parts of the city, that seldom happens. In downtown the hailstones would be rather small. In the city upper parts and on the plateau, the hailstones can get surprisingly big, staying out is dangerous. From April onwards, the weather gets gradually drier and colder. In July the temperatures go below the freezing point at night and during the mornings. Snow storms are rare due to the dryness of the Andes during this period, but every year, one or two of them can be enjoyed.
Global warming has visible effect here. The Chacaltaya Ski Resort - the highest in the world – seldom has snow anymore. Glaciers are melting around the city, and La Paz itself rarely gets any snow. Yet, this July an early snow storm blackened the skies for a couple of days and left the mountains surrounding the city covered in a beautiful white rug. The attached picture shows the delightful result.