Today's weather for Helsinki, Finland9th Nov 2009 02:50

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Weather Overview for Helsinki

Helsinki has a cool climate, exhibiting features of both continental and maritime conditions; the difference in temperature from summer to winter is large, yet it does not get particularly hot, or as cold as might be expected for this latitude. The currents and winds of the North Atlantic Ocean and the Baltic Sea are great moderating factors, influencing all of coastal Finland. Helsinki is particularly prone to these effects as it consists of many bays and peninsulas; the shoreline is disproportionately large and water is abundant. Helsinki is very flat, presenting no obstacle to the wind which also to its susceptibility to maritime conditions, and also means conditions are very changeable from moment to moment. Whatever the average conditions of a given month or season, everything can suddenly change to the unexpected. Sitting so far north, the city does see very long summer days and very short winter days, though the effect is not as extreme as in the north of Finland.

Summer, from June till August, is mild and sometimes warm. The average high temperature rises to 18°C in June and 21°C in July then cools slightly to 20°C in August. These temperatures are not as bad as they might seem; similar average highs are seen in London and Helsinki sees a lot more sun than London does. June sees an average of nine hours of sunshine per day, July and August receive eight and seven respectively. However, these hours of sun are stretched out over longer days. June days are as long as nineteen hours but they start to shorten after the summer solstice (21^st June). The sun doesn’t truly set for two weeks in June, just dipping below the horizon for brief periods of twilight. Night times are cold, around 12°C, and require an extra layer or so. The sea gets just warm enough for a brave dip at 17°C in August. Rainfall increases throughout the season, falling in short, light showers.

Autumn, from September till November, cools down and gets cloudy quite rapidly. The average high temperature drops to a cool 14°C in September then down to 7°C in October and a very chilly 2°C in November. Night time temperatures start falling below freezing around mid October and get to an average low of -2°C in November. Snow often falls in November and frosts are the norm. Rainfall stays at the same level but increases in frequency, falling in light, stubborn showers.

Winter, from December till February, is very cold and rather gloomy. The average high temperature falls below freezing for the entire season, getting down to -1°C in December and -2°C in January and -4°C in February. The average low is rather unpleasant at -7°C in December, -8 in February and -10°C for the rest of the season. If it gets cold enough the Northern Lights, or Aurora Borealis, can be seen. The days shorten to six hours of daylight, with an upsetting one hour of sunshine in December. While days do lengthen after December, January still only sees one hour of sunshine per day and February is hardly better with two. Snow falls on most days covering the city in a thick layer of snow. The sea is very cold at 1°C, though further north it gets down to freezing and Bothnia Bay actually freezes over.

Spring, from March till May, goes from cold to cool and dismal to sunny. The average high temperature gets just above freezing in March at 1°C, when the average low is still at -8°C. Frost and snow is still common in March. The thaw begins in April when the average high gets to 8°C, but the average low of -1°C can see thawed snow freezing again at night creating very icy conditions. The snow is entirely melted by the end of April. May is almost warm with an average high of 14°C, though its average low is still 3°C. Sunshine rushes back; March sees four hours a day, still not fantastic but April sees six and May sees eight.

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