The weather in 2015 was considered unfavourable, except the autumn. The winter was dominated by a series of heavy windstorms, often with snow and rain. Traffic was often interrupted and there was considerable wind damage. The heaviest storm hit on 14 March. In late April, cold and northerly winds set in and persisted until the end of August, often with heavy precipitation in the Northeast and East, but in the Southwest the weather was slightly more favourable. The autumn (September to November) was the most favourable part of the year, until the end of November when there was an unusually heavy snowfall in the Southwest. The weather in December was stormy.
The year 2015 was the coldest in Iceland since 2000, but this period has generally been abnormally warm so the average temperature was close to the 1961-1990 mean. In most parts of the country the precipitation was well above normal.
The average temperature in Reykjavík was 4.5°C, 0.2°C above the 1961-1990 mean. This is the 20th consecutive year above this mean in Reykjavík. But, it was also the coldest since 2000. In Stykkishólmur the average temperature was 4.1°C, 0.6 above the mean, and 3.8°C in Akureyri, also 0.6°C above the mean. In Vestmannaeyjar the mean was 4.8°C, equal to the 1961-1990 mean. In the country as a whole the temperature was 0.5°C above the 1961-1990 mean, but -0.6°C below the mean of the last ten years (2005-2014).
September was the warmest month of the year in about 30 percent of the country. This is unusual, the last time it occurred on this scale was in 1958.
The annual mean was highest in Surtsey, off the Southern coast, 5.8°C, but lowest at Þverfjall (753 m a.s.l) in the Northwest, -2.2°C. Inhabited areas had the lowest annual temperature at Svartárkot, 0.8°C.
The positive deviation from the 1961-1990 mean was largest in Grímsey off the north coast, but smallest at Vestmannaeyjar, off the south coast. The temperature difference between these two stations was unusually small compared to the long term.
A short overview of the individual months
Even though the temperature was above the mean in 1961-1990, January was cold compared to the last ten years. Precipitation was heavy almost all of the country, but not close to records. The weather was changeable.
February was rather cold, at least compared to the last years. The precipitation was above normal in most parts of the country. The weather was very changeable and often violent with blizzards and traffic disruptions; and during a short warm spell there were flood damages.
March was also very windy and the precipitation was heavy in the South and West. The weather was better in the North and East. The temperature was well above the mean of 1961-1990, but below the mean of the last ten years in the South and West. The weather was often bad, with high winds and snowstorms. Extensive wind damages occurred, especially during a very violent windstorm on the 14th.
April and May
The weather was mainly favourable for the first three weeks of April but then became unusually cold for the season. This cold and unfavourable weather lasted the whole of May over all of the country and May was the coldest for more than three decades.
June and July
June was also cold but July colder still, except in a small area in the Southwest where it was dry and sunny in the prevailing north-easterly offshore wind.
August was cold and wet in the northeast but somewhat more favourable elsewhere. The precipitation exceeded earlier monthly totals at a few stations. There were flood damages in the north in the heavy precipitation.
September, October and November
September, October and November were the most favourable months of the year. It was rather warm, especially in September which became the warmest month of the year at many stations in the North and East.
December was a difficult month. There was unusually much snow in the Southwest in the first week of the month and two violent windstorms hit the country. The first, on the 7th and 8th, caused much damage in many parts of the country, the most densely populated areas in the Southwest were mainly spared, though. The second storm, on the 30th, caused both wind- and coastal damage in the East and the pressure dropped down to its lowest value in Iceland since 1989.
Document for the year