Helsinki in August

In August, Helsinki averages 20°C (68°F) during the day and 13°C (55°F) at night, with around 13 days of rain (80 mm total).

Peak season

Conditions are comfortable for sightseeing without being sweltering. Plan for unsettled weather and bring rain gear.

August offers comfortable temperatures in Helsinki, with some rain to plan around.

20°C
Avg high
13°C
Avg low
13
Rain days
80 mm
Rainfall

How August compares to the rest of the year in Helsinki

2nd
warmest month of the 12
6th
wettest month of the 12
12%
of yearly rainfall falls in August
15 h 44 min
daylight on the 15th

August is one of the warmest months in Helsinki (2nd of 12) and moderately rainy compared to the rest of the year (6th of 12). Daytime temperature runs 11°C above the annual average (9°C). August runs 2°C cooler than July (22°C) and cools 5°C in September (15°C).

August sunrise & sunset in Helsinki

🌅
Sunrise (15th)
5:33 AM
🌇
Sunset (15th)
9:16 PM
Day length
15 h 44 min

Times shown for Helsinki local time (Europe/Helsinki), calculated for the 15th of August. They shift by a few minutes day to day across the month.

Photography light in Helsinki — August

Golden-hour and blue-hour windows for the 15th of August, in Helsinki's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).

🌅 Blue hour (AM)
4:33 AM – 5:13 AM
🌄 Golden hour (AM)
5:13 AM – 6:13 AM
🌇 Golden hour (PM)
8:36 PM – 9:36 PM
🌆 Blue hour (PM)
9:36 PM – 10:16 PM

📅 When to book — Helsinki in August

Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on August's tier (Peak season) and Helsinki's popularity.

✈ Flights — lead time
3-5 months
Flight prices are near their annual peak. Watch fare-alert tools, book directly when you see a fare under the typical range for this city.
🏨 Lodging — lead time
3-5 months
Reasonable selection still available at 3-4 months out, but central locations vanish first.

Crowds & pricing — August in Helsinki

Peak season

Helsinki is in peak season during this month — expect bigger crowds at famous sights, higher hotel and flight prices, and longer queues. Restaurant reservations a few days out are advisable, and any boutique hotels you have your eye on should be booked weeks ahead. The trade-off: most attractions, restaurants, and seasonal services are fully open, the weather is at its most reliable, and the city feels at its most alive.

Why this tier: excellent tourism weather Northern Hemisphere summer holidays

Sun & mosquito risk — August in Helsinki

☀️ UV Index (noon, 15th)
8
Very high
Limit sun exposure between 11 AM and 3 PM; SPF 30-50, reapply every 90 minutes outdoors.
🦟 Mosquito risk
●●●○○
Moderate
Active mosquito season. DEET 25-30% repellent recommended, especially at dawn/dusk.

UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.

Sea temperature in Helsinki — August

19.4°C (67°F)
cool
swimmable but bracing — wetsuit helps for long sessions

Across the year Helsinki's sea swings from -0.2°C (January) to 19.4°C (August) — August sits at 19.4°C.

Helsinki in other months

MonthAvg highAvg lowRainfallRain daysSnow days
January -3°C / 27°F -7°C / 19°F 55 mm 17 11
February -3°C / 27°F -8°C / 18°F 40 mm 15 11
March 1°C / 34°F -5°C / 23°F 40 mm 12 7
April 8°C / 46°F 0°C / 32°F 35 mm 11 2
May 15°C / 59°F 5°C / 41°F 40 mm 11 0
June 19°C / 66°F 11°C / 52°F 55 mm 12 0
July 22°C / 72°F 14°C / 57°F 75 mm 12 0
August 20°C / 68°F 13°C / 55°F 80 mm 13 0
September 15°C / 59°F 8°C / 46°F 70 mm 13 0
October 8°C / 46°F 3°C / 37°F 80 mm 15 0
November 3°C / 37°F -1°C / 30°F 70 mm 16 5
December -1°C / 30°F -5°C / 23°F 55 mm 17 9

Other cities with similar August weather

🌍 See the full ranked list of climate twins for Helsinki in August →

Frequently asked questions

How hot is Helsinki in August?

In August, Helsinki averages a high of 20°C (68°F) and a low of 13°C (55°F) — generally mild and pleasant.

Does it rain a lot in Helsinki in August?

August can be fairly wet in Helsinki, with about 13 rainy days on average.

Is August a good time to visit Helsinki?

August is mild and pleasant. It suits travelers who are comfortable with mild and pleasant weather; check the month-by-month ranking to compare it against the rest of the year.

What should I pack for Helsinki in August?

Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full August packing list for Helsinki for a complete, climate-based checklist.

Open Helsinki on the interactive map

Check the live 10-day forecast and sunrise/sunset.