Last updated: August 21, 2025
In May, Helsinki experiences a delightful transition into spring, with temperatures ranging from a maximum of 27°C (80°F) to a refreshing minimum of -3°C (27°F). The city's average temperature rests at a mild 10°C (50°F), making it an ideal time for outdoor exploration. Despite the pleasant warmth, expect occasional rainfall—averaging 56 mm (2.2 in) over approximately 10 days of the month. Humidity levels peak at 75%, contributing to the vibrant greenery that envelops the city. Overall, May is a captivating time to experience the charm and natural beauty of Helsinki.
In May, Helsinki sheds its winter coat, welcoming the warmth of spring with temperatures that range significantly from a chilly -3°C (27°F) at night to a delightful maximum of 27°C (80°F) during the day. The average temperature reaches a comfortable 10°C (50°F), marking a vibrant shift from the lingering cold of earlier months. This transition is evident from April's milder 4°C (39°F), indicating a clear upward trend as the city embraces longer days and blossoming landscapes. As May progresses, the welcoming warmth encourages both residents and visitors to enjoy the outdoors, making it a lively month that hints at the summer to come. The temperate climate not only enhances the beauty of Helsinki but also invites an array of activities, reflecting the spirited essence of this Scandinavian gem in springtime.
May in Helsinki brings the promise of spring with a precipitation total of 56 mm (2.2 in), a slight increase from the previous months. The city experiences about 10 days of rain, aligning closely with April's 9 days, suggesting a continuation of wet weather as the season transitions. This uptick in precipitation marks a subtle shift towards summer, as it sets the stage for June's typically wetter climate. As one of the wetter months in the spring season, May showcases nature's awakening, providing a refreshing backdrop for outdoor activities, albeit with the occasional drizzle. The gradual rise in rainfall hints at warmer days ahead, encouraging both flora and fauna to flourish in the vibrant Finnish landscape.
In May, humidity in Helsinki begins to show a noticeable drop, settling at 75%—a welcome change from the winter months characterized by nearly perpetual dampness, with January's humidity peaking at an impressive 97%. As spring unfolds, the air becomes crisper and lighter, with April also showing improvement at 86%. This decline continues seamlessly into June, which maintains the same 75% level, signaling the onset of summer. The trend suggests a transition towards a more temperate climate, with humidity levels rising again in the warmer months of July and August, where they reach 80% and 83%, respectively. Overall, May marks a pivotal shift, showcasing the gradual easing of humidity that accompanies the blossoming of spring.
As May rolls in, Helsinki experiences a notable increase in the UV Index, reaching 5, which falls into the moderate exposure category. This month's UV Index indicates that while the sun's rays are stronger than in earlier months, the risk of harm from unprotected sun exposure remains manageable. With a burn time of approximately 30 minutes, it's advisable for residents and visitors alike to take precautions such as applying sunscreen and wearing protective clothing, especially during midday when the sun is at its peak. Following May, UV levels rise sharply in June and July, reminding us to stay vigilant as we embrace the warmer, sunnier days. For more details on UV exposure year-round, check out the Helsinki UV Index.
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As May arrives in Helsinki, it marks a vibrant transition into the warmth of summer, capturing 451 hours of sunshine that heralds longer, sunnier days. This is a striking escalation from April's 362 hours, illustrating a steady climb in daylight as spring gives way to the lushness of late spring. Following a long winter, the increasing sunlight not only brightens the cityscape but also ignites outdoor activities and social gatherings, making it a bustling time for locals and tourists alike. The upward trend continues into June, where the sun shines even brighter, with nearly 493 hours, suggesting that the city's embrace of summer is both celebrated and eagerly anticipated. The surge of sunshine in May not only enhances the aesthetic beauty of Helsinki but also uplifts the spirits, ushering in a season filled with potential and joy.
In Helsinki, the likelihood of sunny weather takes a notable turn in May, where the chance of sunshine stands at 31%. While this marks a decline from the 44% chance seen in April, it still represents a significant improvement over the winter months, where sunny days are scarce. As spring progresses into summer, the trend becomes increasingly optimistic; after May, the chances of basking in the sun soar further, peaking in July with a 56% likelihood. This pattern highlights the gradual transition into brighter days, making May a delightful month for those eager to embrace the sun before the peak summer warmth arrives.
As spring transitions into summer, Helsinki experiences a remarkable surge in daylight duration throughout May, basking in 17 hours of sunlight. This increase marks a significant shift from the preceding months, where daylight is limited to just 6 hours in January and gradually expands to 14 hours in April. The steady elongation of days signals the arrival of warmer weather and vibrant outdoor activities. Following May, the daylight reaches its zenith in June with 18 hours, before slowly receding as summer gives way to autumn, illustrating the pronounced seasonal rhythm of Finland's Nordic climate.
In May, the winds in Helsinki present a gentle transition from the briskness of spring, with an average speed of 3.7 m/s (8 mph). While not the windiest month, May's breezes hint at the seasonal shift, offering a pleasant backdrop to the budding greenery and blossoming flowers around the city. This decrease in wind speed compared to the higher gusts of earlier months like March and April highlights a softening atmosphere, leading into the calmer summer months ahead. As the year progresses towards June, the winds continue to mellow, reinforcing a sense of serenity that envelops the capital during this beautiful time of year.
Weather in Helsinki varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Helsinki, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather of May and January, one can observe a striking contrast. May brings a more temperate climate, with average temperatures around 10°C (50°F) and highs reaching up to 27°C (80°F), while January remains frigid, characterized by a chilling average of -3°C (28°F) and a maximum that seldom exceeds 8°C (46°F). Despite similar levels of precipitation—56 mm (2.2 in) in May compared to 55 mm (2.2 in) in January—the distribution differs slightly, with January experiencing precipitation on 11 days versus May's 10 days. Additionally, January’s humidity is significantly higher at 97%, compared to May’s more comfortable 75%. For further details on Helsinki's cold winter climate, you can refer to Helsinki weather in January.
May and February present stark contrasts in weather conditions. In May, temperatures range from a chilly minimum of -3°C (27°F) to a pleasant high of 27°C (80°F), with an average of 10°C (50°F). As spring arrives, precipitation measures around 56 mm (2.2 in) over about 10 days, and humidity sits at a moderate 75%. In contrast, February is much colder, with temperatures dipping as low as -23°C (-8°F) and reaching a maximum of only 6°C (43°F), averaging -3°C (26°F). The month also sees around 48 mm (1.9 in) of precipitation over 10 days, accompanied by a high humidity level of 95%. For more details, you can check out Helsinki weather in February.
The weather in March is notably colder than in May, with minimum temperatures plummeting to -22°C (-7°F) compared to May’s milder -3°C (27°F). March has an average temperature of -1°C (31°F), while May enjoys a more pleasant average of 10°C (50°F), reaching a maximum of 27°C (80°F). Additionally, March experiences slightly less precipitation with 52 mm (2.0 in) over 12 days, compared to May’s 56 mm (2.2 in) spread across 10 days. The humidity in March is also higher at 93%, making the cold feel even more intense, while May’s humidity averages 75%. For more detailed information, you can visit Helsinki weather in March.
In comparing the weather of May and April, May generally presents milder temperatures and more significant warmth. While April experiences colder temperatures, with a minimum of -12°C (10°F) and an average of just 4°C (39°F), May sees a notable rise, with a minimum temperature of -3°C (27°F) and an average of 10°C (50°F). Additionally, the maximum temperatures in May can reach up to 27°C (80°F), significantly higher than April's maximum of 19°C (67°F).
Precipitation levels are slightly higher in May, totaling 56 mm (2.2 in) over 10 days compared to April's 48 mm (1.9 in) over 9 days. However, April's humidity is noticeably higher at 86%, compared to May's 75%. For more detailed information on April conditions, you can visit Helsinki weather in April.
In May, temperatures range from a chilly minimum of -3°C (27°F) to a pleasant average of 10°C (50°F), peaking at 27°C (80°F) on warmer days. The month also brings some rainfall, with 56 mm (2.2 in) of precipitation spread over about 10 days, while humidity remains relatively high at 75%.
In contrast, June typically experiences milder weather, with minimum temperatures starting at 3°C (38°F) and averaging around 16°C (62°F), eventually reaching a maximum of 30°C (86°F). Precipitation slightly increases to 61 mm (2.4 in) over the same number of days, yet the humidity remains constant at 75%. For more detailed information, check Helsinki weather in June.
May and July exhibit notable differences in weather patterns. In May, temperatures range from a chilly minimum of -3°C (27°F) to a maximum of 27°C (80°F), with an average temperature of around 10°C (50°F). The month sees approximately 56 mm (2.2 in) of precipitation over 10 days, with humidity levels at 75%. In contrast, July experiences milder minimum temperatures of 8°C (46°F) and significantly warmer averages of 18°C (65°F), peaking at 32°C (90°F). However, July also brings increased rainfall, totaling about 91 mm (3.6 in) over 13 days and slightly higher humidity at 80%. For more detailed insights, check out Helsinki weather in July.
May and August present distinctly different weather patterns. In May, temperatures range from a chilly minimum of -3°C (27°F) to a pleasant maximum of 27°C (80°F), with an average temperature of 10°C (50°F). The month experiences moderate precipitation of 56 mm (2.2 in) over about 10 days and maintains a humidity level of 75%. In contrast, August sees a noticeable rise in warmth, with minimum temperatures of 7°C (45°F) and maximum temperatures reaching 29°C (84°F), resulting in an average of 17°C (62°F). However, it also brings increased rainfall, totaling 83 mm (3.3 in) over approximately 13 days and a higher humidity level of 83%. For a more detailed look at the weather in August, you can visit Helsinki weather in August.
In May, the weather begins to warm up, with temperatures ranging from a chilly -3°C (27°F) at night to a pleasant max of 27°C (80°F) during the day, averaging around 10°C (50°F). May experiences about 56 mm (2.2 in) of precipitation over approximately 10 days, with a humidity level around 75%.
In contrast, September brings slightly cooler average temperatures, with a minimum of -1°C (31°F) and a maximum of 23°C (73°F), averaging around 12°C (54°F). However, it is more humid, reaching 90%, and sees increased precipitation of 76 mm (3.0 in) spread over 13 days. For more specific insights on September weather patterns, you can check out Helsinki weather in September.
In comparing the weather of May and October, we notice significant differences in temperature and precipitation. May experiences a wider temperature range, with minimums around -3°C (27°F) and maximums reaching up to 27°C (80°F), resulting in an average of 10°C (50°F). In contrast, October sees chillier conditions, with minimum temperatures dropping to -4°C (25°F) and maximums only reaching 16°C (62°F), averaging at 7°C (45°F). Additionally, October tends to be wetter, with 89 mm (3.5 in) of precipitation spread over 17 days, compared to May's 56 mm (2.2 in) over just 10 days. The humidity also increases from 75% in May to 93% in October, making the fall month feel much more damp. For more details, you can check Helsinki weather in October.
May and November present distinctly different weather patterns. In May, temperatures vary from a minimum of -3°C (27°F) to a maximum of 27°C (80°F), with an average of 10°C (50°F). The month typically sees about 56 mm (2.2 inches) of precipitation over approximately 10 days, accompanied by a moderate humidity level of 75%. In contrast, November experiences chillier conditions, with temperatures ranging from -7°C (19°F) to a maximum of 12°C (54°F) and an average of just 3°C (38°F). This month is slightly wetter, with around 62 mm (2.5 inches) of precipitation spread over roughly 13 days, and significantly higher humidity at 94%. For a closer look at November weather specifics, you can check Helsinki weather in November.
May and December present stark contrasts in weather characteristics. In May, temperatures range from a refreshing minimum of -3°C (27°F) to a pleasant maximum of 27°C (80°F), with an average of 10°C (50°F), and the humidity sits at a moderate 75%. Precipitation is relatively mild, totaling 56 mm (2.2 in) over about 10 days. Conversely, December is much colder, with temperatures ranging from a frigid minimum of -18°C (0°F) to a maximum of 7°C (44°F), averaging around -1°C (31°F). The month experiences higher precipitation at 73 mm (2.9 in) across approximately 15 days, accompanied by increased humidity levels of 95%. For more details on winter conditions, you can check Helsinki weather in December.
As spring unfolds, May in Helsinki presents a delightful contrast to the cooler months, with temperatures gradually warming up and reaching a pleasant average of 10°C. While occasional chilly days can still dip below freezing, the city experiences a significant shift towards longer days and increased sunshine, inviting outdoor activities. However, with about 10 days of rain totaling 56 mm, it's wise to carry an umbrella. The humidity remains relatively high at 75%, adding a refreshing touch to the air. Embrace the beauty of May as the city begins to bloom, making it an ideal time to explore. For more insights, visit Helsinki Climate.