Tierra del Fuego weather is quite unique. This has everything to do with the archipelago’s location. Split between Argentina and Chile, the islands of the Tierra del Fuego form the southern tip of the South American continent. The oft-rough waters of the Drake Passage separate the Tierra del Fuego from Antarctica to the south. On the eastern side is the Atlantic Ocean, while the western coast borders the Pacific Ocean.
Because of its extremely southern location, the Tierra del Fuego region is quite chilly on the whole. That being said, the sea and the mountains do their part to keep things relatively moderate throughout the year. The climate of the region is described as oceanic, though there are some areas that better fit under the sub antarctic or polar classification. In fact, the southernmost reaches of the Tierra del Fuego could be described as having a climate that is similar to that of Iceland or the Alaska Peninsula.
In general terms, the Tierra del Fuego region has summers that are short and cool. Winter is a longer season and could be described as being wet and mild. Unstable is perhaps the word that best describes autumn and spring.
The Argentinean city of Ushuaia and the Chilean city of Punta Arenas are good reference points for Tierra del Fuego temperature breakdowns. In the summer, the nighttime temps in Ushuaia, for instance, typically range between 42 and 50 degrees Fahrenheit, while the daytime temps usually fall between 46 and 64 degrees. In autumn, it is usually between 32 and 42 degrees at night, and 41 to 50 degrees during the day. Winter sees the temperatures in Ushuaia typically ranging from 5 to 17 degrees at night, and 28 to 41 degrees during the day. Finally, the temperatures range between 35 and 44 degrees for a typical spring night in Ushuaia, while the spring daytime temps tend to fall somewhere between 39 and 52 degrees.