Argentina is the second largest country in Latin America, stretching from the tropical jungles of its northern border with Brazil, to Antarctica in the far South. As such its climate and weather conditions vary greatly from region to region. Spring (Sep-Nov) is a great time to visit most of the country, while mid-summer (Dec-Jan) is the perfect time to head to Southern Patagonia. Autumn (April-May) is wine harvesting season in Mendoza. The lowland areas of the North should be avoided in the height of summer and conversely the far South is best left alone in mid-winter, though this is the perfect time to visit the ski resorts in the Patagonian Andes. The country can be split more or less into four broad climatic regions - the Eastern and central region (Pampas); the Northeastern interior; Western Argentina and Southern Argentina (Patagonia). The distinctive mountain climate of the high Andes can also be added.
Eastern and Central Argentina
Eastern and central Argentina (including Buenos Aires) also known as the Pampas, has a rainfall of 500mm to1000 mm per year. The area has mild winters and warm summers with more rainfall during the summer months concentrated into heavy downfalls that last for a short period of time. Average daily maximum temperatures in Buenos Aires range from 14 °C (57 °F) in June and July to 29 °C (85 °F) in January.
The Northeastern Interior
The Northeastern interior has a warmer climate than the Pampas and in the far north it is tropical, or near tropical. Temperatures remain quite high throughout the year, average daily maximums varying from 21 °C (70 °F) in winter to 36 °C (97 °F) in January.
Western Argentina
Western Argentina is a very dry region. Even on the highest peaks snowfall is light. The eastern slopes and foothills of the Andes form a semi-arid region and the lowlands are virtually deserts. Annual rainfall of less than 250 mm is not uncommon. Droughts are frequent and often prolonged. Rainfall is more frequent in the summer months, which are often hot and sunny. In Mendoza daily average maximum temperatures range from 15 °C (59 °F) in winter to 32 °C (90 °F) in summer.
Southern Argentina
Southern Argentina is a dry region with a cool temperate climate, cold in the far South. Towards the west of the region, rainfall is greater as cloud spills over the western side of the Andes. In the extreme South, the summers are distinctly cool. The winters are long with frequent frost and snow, but the ocean's influence ensures that the cold is never prolonged or severe. Temperatures in Ushuaia range from -3°C (26°F) in winter to 14°C (57°F) in summer.