Generally the best conditions are from late July through mid September. August is a great month to visit either Chile or Argentina. When it is blistering hot in North America, escaping to South America in August provides the perfect opportunity to cool off. The famous Santa Rosa storm generally hits sometime between the last week of August and the first 2 weeks of September. September is an excellent month to tour the Chilean volcanoes or to visit Ushuaia, which in big seasons can be skied until November. School holidays are the last 2 weeks of July and the resorts are busier during that period but there is no problem seeking out fresh tracks. Throughout the season conditions can range from big Andean powder storms to bluebird spring corn days.
Countries outside of the EU, Switzerland, Canada and the USA may require visas. Check with the Argentine Consulate in your country for all the necessary requirements.
To Enter Chile:
Although no Visa is required, there is a one-time reciprocity fee for US, Australian and Canadian passport holders to enter Chile. The fee is charged at the airport upon arrival at the Chilean customs line. US and Canadian citizens must pay the $132.00 “Tourist Tax” charged at Chilean customs. Australian citizens must pay $61.00 to enter. This tax must be paid in cash in US dollars at Chilean customs upon entry. It is paid once and remains valid until the passport expires (for Americans and Canadians) and 3 months for Australians.
All travelers are required to have valid passports and CASA recommends carrying a photocopy of your passport at all times.
For those who have more time on their hands, the Southern Cross and Endless Winter provide extended itineraries and are a great value.