May 18 is generally a great time to visit Helsinki. While there is a slight chance of rain (16%), showers are usually brief. Expect comfortable 12°C weather. Take advantage of the off-peak calm in Helsinki to see the sights without the usual crowds.
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Essential Travel Info for Helsinki
Currency
EUR
€ Euro
Language
Finnish
+1 more
Driving
Right side
Connect
Much of Helsinki is blanketed withWi-Fi ...
Safety
Very High Safety
GPI: 1.439
Helsinki Weather Forecast for May 18
"Mild & Comfortable. Expect average highs of 12.3°C. 16% chance of rain."
What to Wear in Helsinki in May
Based on historical data for May 18, Helsinki typically experiences temperatures between 6.8°C and 12.3°C. We recommend packing heavy coat, scarf, gloves to stay comfortable. Trends suggest it will stay mostly dry (16% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Helsinki
Smart Suitcase
- Heavy Coat
- Scarf
- Gloves
Average High
12.3°C
Daytime Peak
Average Low
6.8°C
Nighttime Low
Feels Like
11.2°C
🌤️ Minor difference
Rain Chance
16%
Avg 0.8mm if it rains
Cloud Cover
57%
Overcast
Pressure
1014.3 hPa
Medium volatility
Helsinki Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 98% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
03:00 - 10:00
16:00 - 20:00
Type I-II
🔴 24 min to burn
Type III-IV
🟡 36 min to burn
Type V-VI
🟢 60 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
7.8°C
Dry air
Heat Stress
Low
No heat warning
😐 Best outdoor time:
Any time during daylight hours
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
❄️ Cold Water Hazard
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Finland
Flight Traffic
Quiet
38/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~232
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Helsinki
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
03:36
☀️ Noon
12:18
🌇 Sunset
20:59
⏱️ Daylight
17h 23m
Wind Speed
19.6 km/h
Gentle breeze
Sunshine
12.3 hrs
Direct Sun (Cloud-free)
Humidity
74%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Helsinki
Smart Flight Estimator
Airport-to-Airport Logistics
unlock smart flight estimates
Add your home location in settings to see airport details.
Travel Health & Safety in Helsinki
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Moderate fluctuations. Some sensitivity possible.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is excellent. Perfect for outdoor activities.
Regional Safety Profile
Seismic Activity
Zero seismic activity detected in 30 years.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Helsinki on May 18 averages 12.3°C with a 16% precipitation probability. Wedding/Outdoor Event Score: 82/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Helsinki Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
May 22
13.1°C • 15% rain
Score
92
May 20
12.8°C • 14% rain
Score
90
May 19
12.6°C • 14% rain
Score
89
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (May 18) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Helsinki Worth Visiting on May 18?
Planning a trip to Helsinki on May 18? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year offers a bracing seasonal atmosphere averaging 12.3°C with a 16% historical precipitation risk.
✈️ Travel Logistics: Approximately 232 landing slots available daily during this period, indicating peak tourist activity.
💉 Health Advisory: 8 vaccinations are recommended for Finland, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 10.3°C (polar plunge). Wave conditions are generally lake-like with heights around 0.4m.
📊 Historical Extremes: The hottest May 18 recorded in the last 30 years saw temperatures hit 14.5°C in 2021, while the coldest dropped to 3°C in 2020.