Surely many times you have heard the phrase “In Patagonia you can have the 4 seasons of the year in the same day” and the reality is that… yes, it is totally true! We can start the day with a bright sun and a pleasant temperature, arriving at noon we start to see a couple of clouds and the unmentionable (the one that blows a lot) appears. In the afternoon we feel some drops falling and the temperature drops abruptly, although probably as we continue the march we begin to feel warm because of the radiant sun that reappeared at one moment to another…
So, if you are thinking of visiting El Chaltén or any other destination in Patagonia, we recommend that you come prepared for any kind of weather, and this rule applies to any season of the year.
If there is something that characterizes Patagonia, it is its wind gusts. They can be greater or lesser depending on the time of year (mainly they tend to exist in major extent the months corresponding to the spring and summer), so a windbreaker in the backpack is almost a must.
On the other hand, we have the precipitations that tend to be higher during the fall (mid-March to late May), and then turn into snow come winter (although it is not uncommon to see snow or water-snow at the end of February – March).
And finally the temperature: As in the entire southern region of Argentina, temperatures tend to be low during most of the year. As an example, the annual average is around 7-8º, while the average in July (mid-winter) is 0º and the average temperature in January is 13º.
Focusing mainly on the summer months, we have that the average temperature is around 13º, and can drop to 7º (the thermal sensation at dawn in the mountains can reach 0º) and with highs of up to 20º on a day with lots of sun and no wind.
As we have seen so far, we have no way of knowing exactly what the weather will be like during our outings. However, we can make use of some tools that will allow us to have an overview of how it will be that day:
FOR RAINFALL AND TEMPERATURE:
In my experience, the combination WINDY + YR.NO is the one that performs best in the area of El Chaltén. But when planning an outing, it is recommended to consult the 4 options.
On the other hand, it is not advisable to be guided by data beyond 48 – 72 hs (there may be some variations), so predictions between 24 and 48 hs are usually the most “accurate”.