Helsinki climate
Helsinki (Finland) has a warm-summer humid continental climate (Köppen Dfb). The average temperature over the year is 6 °C43 °F, and about 712 mm28 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Helsinki climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | −129 | −524 | −327 | 562.2 | 24 |
| Feb | −228 | −622 | −425 | 451.8 | 24 |
| Mar | 032 | −326 | −229 | 421.6 | 25 |
| Apr | 541 | 133 | 337 | 411.6 | 9 |
| May | 1152 | 643 | 947 | 481.9 | 0 |
| Jun | 1560 | 1152 | 1356 | 662.6 | 0 |
| Jul | 1967 | 1560 | 1763 | 592.3 | 0 |
| Aug | 1966 | 1560 | 1763 | 712.8 | 0 |
| Sep | 1559 | 1253 | 1356 | 632.5 | 0 |
| Oct | 948 | 643 | 745 | 803.2 | 1 |
| Nov | 440 | 236 | 338 | 753.0 | 7 |
| Dec | 134 | −229 | 032 | 672.6 | 18 |
| Year | 1967 | −622 | 643 | 71228 | 108 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 93% | 82% | 0.3 | 6:37 |
| Feb | 94% | 79% | 0.8 | 9:00 |
| Mar | 90% | 69% | 2.2 | 11:34 |
| Apr | 85% | 67% | 3.8 | 14:29 |
| May | 81% | 62% | 5.2 | 17:09 |
| Jun | 81% | 66% | 5.4 | 18:52 |
| Jul | 81% | 64% | 5.2 | 18:08 |
| Aug | 80% | 63% | 4.0 | 15:38 |
| Sep | 83% | 67% | 2.4 | 12:44 |
| Oct | 87% | 78% | 1.1 | 9:57 |
| Nov | 90% | 85% | 0.3 | 7:20 |
| Dec | 92% | 84% | 0.1 | 5:51 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Helsinki is like
The warmest month is July, with an average high of 19 °C67 °F and a low of 15 °C60 °F. The coldest is February, when highs average −2 °C28 °F and lows −6 °C22 °F. Seasons are strongly marked: the warmest month is on average 21.5 °C38.7 °F warmer than the coldest.
Annual precipitation is moderate at about 712 mm28 in. Rain is spread fairly evenly through the year. The wettest month is October (80 mm3.2 in), the driest is April (41 mm1.6 in).
Relative humidity ranges from 80% in August to 94% in February. The clearest skies (lowest average cloud amount, 62%) are typical of May. Average wind speed near the ground ranges from 9 km/h (5 mph) in May to 17 km/h (11 mph) in December. Daylight lasts from about 5.9 hours in December to 18.9 hours in June.
A lasting snow cover is typical in December–March, when the average snow depth in the reanalysis exceeds 10 cm (deepest in February, about 18 cm).
Best time to visit Helsinki
Based on these averages, the most comfortable months for sightseeing and outdoor activities are July and August: average highs of 19 °C66 °F to 19 °C67 °F with 59 mm2.3 in to 71 mm2.8 in of precipitation per month.
The most challenging month is February, which is cold, with average highs of −2 °C28 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Helsinki
- Winter (December–February) — highs −228 to 1 °C34 °F, lows −622 to −2 °C29 °F, about 56 mm2.2 in of precipitation a month. Pack a winter coat, hat, gloves and warm, non-slip boots and shoes with good grip, as frost is common.
- Spring (March–May) — highs 032 to 11 °C52 °F, lows −326 to 6 °C43 °F, about 44 mm1.7 in of precipitation a month. Pack a warm coat, layers and closed shoes.
- Summer (June–August) — highs 1560 to 19 °C67 °F, lows 1152 to 15 °C60 °F, about 65 mm2.6 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket.
- Autumn (September–November) — highs 440 to 15 °C59 °F, lows 236 to 12 °C53 °F, about 73 mm2.9 in of precipitation a month. Pack a warm coat, layers and closed shoes.
How Helsinki compares
Compared with Saint Petersburg, about 300 km to the east, Helsinki is on average 1.7 °C3 °F warmer and receives 11% less precipitation (712 mm28 in vs 800 mm31 in). The difference is largest in January (5.9 °C10.7 °F warmer).
Of the 9 places in Finland covered by World Climates, Helsinki is the warmest by annual mean temperature and the 9th wettest by annual precipitation. See all of them on the Finland climate page.
Places in other countries with the most similar temperature and rainfall pattern: Tallinn (Estonia, Dfb), Sollentuna (Sweden, Dfb) and Stockholm (Sweden, Dfb).
Nearby places
- Vantaa 15 km · 5 °C42 °F · 733 mm29 in
- Espoo 16 km · 6 °C43 °F · 727 mm29 in
- Tallinn 82 km · 6 °C43 °F · 685 mm27 in
- Lahti 99 km · 4 °C40 °F · 746 mm29 in
- Turku 150 km · 6 °C42 °F · 723 mm28 in
- Tampere 160 km · 4 °C40 °F · 776 mm31 in
- Jyväskylä 234 km · 4 °C39 °F · 807 mm32 in
- Mariehamn 277 km · 7 °C45 °F · 649 mm26 in
Frequently asked questions
What is the warmest month in Helsinki?
July is the warmest month in Helsinki, with an average high of 19 °C (67 °F) and an average low of 15 °C (60 °F).
What is the coldest month in Helsinki?
February is the coldest month, with an average high of -2 °C (28 °F) and an average low of -6 °C (22 °F).
When does it rain the most in Helsinki?
October is the wettest month with about 80 mm (3.2 in) of precipitation; April is the driest with about 41 mm (1.6 in).
What is the best time to visit Helsinki?
Judging by long-term averages, the most comfortable months are July and August.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.