Buenos Aires and the Pampas are temperate; cold in winter, hot and humid in summer.
The deserts of Cuyo, which can reach temperatures of 45°C, are extremely hot and dry in summer and moderately cold and dry in winter. Spring and autumn often experience rapid temperature changes; several days of extremely hot weather may be followed by several days of cold weather, before becoming extremely hot again.
In the Andes, it is cool in summer and very cold in winter, depending on the altitude.
The climate in northwest Argentina varies with altitude, with warm summers and mild winters in the lowlands and freezing conditions at the highest altitudes.Salta and San Salvador de Jujuy are located in valleys and are characterised by a pleasant year-round climate.
Mesopotamia, in the north-east, has a humid climate with abundant rainfall and high temperatures throughout the year.
Patagonia is cool in summer and cold in winter. Much of the region is desert, except in the far west where rainfall is higher and forests are maintained. Rainfall varies greatly over a short distance, from over 1,000 mm to just under 200 mm within 100 km to the east. The climate is characterised by strong and persistent winds that blow across the region, giving the impression that the temperature is much colder than it should be. Extreme temperature variations in the space of a day are even more common here, so pack a variety of clothes and dress in layers.
Remember that the seasons are reversed from those in the northern hemisphere.