Iceland’s climate often surprises visitors. Despite its name and high latitude, the island experiences more moderate weather than commonly imagined. This unique climate results from an interplay between its geographic location and influential ocean currents, creating a dynamic and rapidly shifting environment.
Defining Iceland’s Climate
Iceland’s climate is primarily classified as subpolar oceanic (Köppen classification: Cfc) along its coastal areas, transitioning to a tundra climate (ET) in the interior highlands. This categorization might seem counterintuitive given its proximity to the Arctic Circle. The significant moderating factor is the North Atlantic Current, an extension of the Gulf Stream, which carries warmer waters from lower latitudes towards Iceland. This current helps keep coastal areas relatively mild, especially in winter.
However, Iceland’s high latitude brings colder air masses and long periods of winter darkness, preventing high summer temperatures. The convergence of these influences creates an unpredictable climate. Strong winds are a defining characteristic, often making perceived temperatures feel much colder. This results in mild winters, cool summers, and frequent, sudden weather changes.
Seasonal Weather Patterns
Winters (late November to early March) are mild for the latitude, with average Reykjavik temperatures from -0.5°C to 3°C (31-37°F). Snow is common in northern and highland areas, while coastal regions often see rain. Daylight hours are short, with Reykjavik experiencing only 4 to 5 hours of sunlight in December.
Spring (March to May) sees temperatures gradually climb, reaching an average of 3°C to 9°C (37-48°F) in Reykjavik by May. Precipitation remains frequent, though snow becomes less common at lower elevations as days lengthen. By late May, daylight extends to around 16 hours.
Summers (late May to early September) are cool, with average daytime temperatures in Reykjavik typically ranging from 10°C to 13°C (50-55°F). Temperatures can occasionally reach 20-25°C (68-77°F). A notable feature is the “Midnight Sun,” where daylight can last for nearly 24 hours, especially in June and July.
Autumn (September to November) brings cooler temperatures and increased rainfall. Average temperatures in September range from 5°C to 10°C (41-50°F). Daylight hours diminish rapidly, from approximately 13 hours at the start of September to around 9 hours by its end. Strong winds are constant throughout all seasons, averaging 11.6 mph and contributing to the perceived cold.
Regional Variations
Iceland’s climate varies regionally due to topography and ocean currents. Coastal areas are generally milder, wetter, and windier than the interior highlands. The highlands are significantly colder, receive more snow, and have more extreme weather.
The South coast, including Reykjavik, benefits directly from the North Atlantic Current, making it warmer and wetter, with average annual temperatures around 6°C. The North coast is colder and drier, averaging 3°C annually, and typically sees more consistent winter snowfall.
Dispelling Common Misconceptions
A frequent misconception is that Iceland is perpetually covered in ice and snow. While glaciers exist and winter brings ample snowfall, much of the landscape, especially coastal areas, remains green for a significant portion of the year. This contrasts with Greenland, which lives up to its icy name, while Iceland surprises visitors with its unexpected greenery.
Another common misunderstanding concerns weather stability. Many expect consistent conditions, but Iceland’s weather is notoriously fickle. It is common to experience sunshine, rain, and strong winds all within a single day, regardless of the season. Therefore, layered and waterproof clothing is always recommended.