Weather in Helsinki

Planning your day in Helsinki or simply curious about the weather conditions? In this section, you will find the most up-to-date information, including detailed forecasts and helpful charts, to keep you abreast of all changes.

The climate in Helsinki can be described as humid continental, with a noticeable influence from the Baltic Sea. This means the city experiences four distinct seasons, each with its own weather characteristics, offering diverse experiences for travellers throughout the year. Here, you can expect real snowy winters and comfortably warm summers.

Winters in Helsinki are generally cold, with average temperatures below freezing from December to March, with January and February being the frostiest months. Spring brings gradual warming, and by May, the temperature becomes more comfortable for walking. Summer, from June to August, is usually moderately warm and pleasant, with average temperatures around +16°C to +18°C, ideal for exploring the city and its numerous islands. In autumn, from September to November, the weather gradually becomes cooler, painting the parks in golden and crimson hues.

As for precipitation, it is distributed quite evenly throughout the year, although the total amount is small – averaging about 2-3 mm per month. However, the number of days with precipitation (rain or snow) is quite significant, ranging from 8 to 16 days per month. This means you can expect frequent but usually not heavy precipitation, whether it be a refreshing summer rain or light winter snow, adding charm to the Finnish capital.

The temperature regime in Helsinki demonstrates a clear change of seasons, offering diverse weather conditions throughout the year. The coldest months are traditionally January and February, when the average temperature holds at -3.4°C...-3.5°C, and minimum values can drop to -5.5°C...-5.8°C. In contrast, the warmest period falls in July, with an average temperature of about +17.6°C and maximum daytime readings reaching +21.2°C. Thus, the annual temperature course reflects a classic temperate climate with cool winters and warm summers.

The summer months in Helsinki, from June to August, are characterized by pleasantly warm weather. Average daytime temperatures range from +16.0°C in June to +17.6°C in July, with maximum values usually in the +20°C...+21°C range. Nights bring refreshing coolness: minimum temperatures in summer range from +12.0°C to +14.1°C. This creates comfortable conditions for long walks and exploring the city. The difference between day and night temperatures in summer is quite perceptible, averaging 7-8°C, which allows for a break from the daytime warmth.

Winter in the Finnish capital, covering the period from December to February, is genuine, with stable sub-zero temperatures. Average values range from -1.5°C in December to -3.5°C in February. Night frosts can reach -5.8°C, while during the day the thermometer rarely rises above -1.2°C in the coldest months, and in December it may approach zero. Daily temperature fluctuations in winter are less pronounced than in summer, amounting to about 4-5°C. The transitional seasons – spring and autumn – are distinguished by gradual temperature changes: April already pleases with positive values (averaging +3.8°C, with highs up to +7.6°C), and October brings noticeable coolness (averaging +6.9°C), preparing the city for the winter period.

Precipitation in Helsinki is distributed throughout the year, however, the total amount in each month is extremely small, usually amounting to just 1 to 3 mm. Despite this, the number of days with precipitation is quite significant, indicating frequent but, as a rule, very light precipitation, such as drizzle, light rain, or weak snow. There is no pronounced dry season in the city; rather, one can speak of periods with more or less frequent, but always insignificant in volume, precipitation.

The character of precipitation changes depending on the season. In winter, especially from December to March, when average temperatures drop below freezing (January and February are the coldest months), precipitation falls mainly in the form of light snow or snow pellets. January and December stand out with the highest number of days with such precipitation – 16 days each. In spring, especially in April, the amount of precipitation is minimal (only 1 mm and 8 wet days), and it shifts to the form of light rain. In summer, from June to August, it rains, however, it is usually short-lived and not heavy; July and August, along with October, receive slightly more precipitation (3 mm). At the same time, July is also distinguished by a high frequency of rainy days (15 days).

In autumn, from September to November, light rains prevail, but as winter approaches, in November, mixed precipitation in the form of rain with snow is possible, also insignificant in intensity. October also belongs to the months with frequent but light precipitation (15 days). Thus, if frequency is taken into account, the "wettest" months can be called January, December, July, and October, although even during these periods the total amount of falling moisture remains small. April is the month with the lowest frequency and volume of precipitation.

When packing for Helsinki, it is important to consider the changeable weather and the noticeable change of seasons. The basis of your wardrobe should be layered clothing. In winter (from December to March), when average temperatures drop below freezing and the number of days with snow reaches 16 per month, you will need warm clothes: thermal underwear, a fleece jacket, a windproof and waterproof winter jacket, a hat, a scarf, gloves, and insulated waterproof shoes. Even if there is little snow, it can be frequent, so protection from moisture and cold is critical.

In spring (April-May) and autumn (September-November), the weather can be unpredictable. In April, the driest month, it is already warmer but still cool, so a light jacket, sweater, and comfortable shoes will come in handy. By May and in September, temperatures are more comfortable, but evenings can be cool. For this period, a mid-season jacket (preferably waterproof, as the number of days with precipitation is still significant), jumpers, and comfortable boots or sneakers are recommended. Don't forget an umbrella or raincoat, as light precipitation is a common occurrence, especially in October and November.

In summer (from June to August), Helsinki is usually pleasantly warm, with average temperatures around +16°C to +18°C. Light trousers or shorts and T-shirts are suitable for daytime walks. However, even in summer, it is worth taking a light jacket or sweater for evening walks or in case of windy weather by the sea. Given that in July and August there are up to 15 days with light precipitation, a compact raincoat or umbrella will not go amiss. Comfortable walking shoes are an absolute necessity at any time of the year, as the city invites long explorations on foot. Sunscreen and sunglasses will also be useful on clear summer days.