Iceland Climate Guide - What to Expect Year-Round

Iceland's climate is classified as subarctic oceanic (Köppen: Cfc) in the south and tundra (ET) in the highlands. The North Atlantic Current (an extension of the Gulf Stream) keeps coastal temperatures 10–15°C warmer than other locations at 64–66°N latitude — Reykjavík's January average of 0.5°C is milder than New York City's. Mean annual temperature is 4.3°C in Reykjavík, 3.2°C in Akureyri, and -2°C in the central highlands. Annual precipitation varies dramatically: Reykjavík receives ~830 mm, the southern coast gets 1,500–3,000 mm, and the rain shadow northeast receives only 400 mm. Wind is the dominant weather factor — average year-round wind speed in Reykjavík is 18 km/h, with winter storms regularly exceeding 90 km/h. Daylight extremes define the experience: summer solstice (June 21) brings ~21 hours of light in Reykjavík and 24 hours of midnight sun in Grímsey island; winter solstice (December 21) gives only ~4 hours of daylight. The weather is notoriously changeable — Icelanders say "if you don't like the weather, wait five minutes." The Icelandic Met Office (vedur.is) provides forecasts updated every 3 hours.