September 21 is statistically one of the best days of the year in Stockholm. With minimal rain risk (14%) and pleasant highs of 15°C, it's ideal for outdoor adventures. As it's peak season for Stockholm, we recommend booking your stay well in advance to secure the best rates.
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Essential Travel Info for Stockholm
Currency
SEK
kr Swedish krona
Language
Swedish
Driving
Right side
Connect
As of Sept 2021, central Stockholm has 5...
Safety
High Safety
GPI: 1.564
Stockholm Weather Forecast for September 21
"Mild & Comfortable. Expect average highs of 15.3°C. 14% chance of rain."
What to Wear in Stockholm in September
Based on historical data for September 21, Stockholm typically experiences temperatures between 9.4°C and 15.3°C. We recommend packing light jacket, long pants to stay comfortable. Trends suggest it will stay mostly dry (14% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Stockholm
Smart Suitcase
- Light Jacket
- Long Pants
Average High
15.3°C
Daytime Peak
Average Low
9.4°C
Nighttime Low
Feels Like
15.3°C
🌤️ Feels accurate
Rain Chance
14%
Avg 0.7mm if it rains
Cloud Cover
64%
Overcast
Pressure
1014.8 hPa
High volatility
Stockholm Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 95% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 15 for extended outdoor time
Type I-II
🔴 47 min to burn
Type III-IV
🟡 71 min to burn
Type V-VI
🟢 118 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
11.9°C
Pleasant
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
⚠️ Mixed Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Sweden
Flight Traffic
High
96/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~318
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Stockholm
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
05:30
☀️ Noon
11:42
🌇 Sunset
17:54
⏱️ Daylight
12h 23m
Wind Speed
16.9 km/h
Gentle breeze
Sunshine
7.9 hrs
Direct Sun (Cloud-free)
Humidity
80%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Stockholm
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 Stockholm
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Rapid pressure changes detected. High risk for meteosensitive people.
Weather unlikely to affect joint pain.
Fish are active due to pressure changes.
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, Stockholm on September 21 averages 15.3°C with a 14% precipitation probability. Wedding/Outdoor Event Score: 93/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Stockholm Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
September 23
15°C • 13% rain
Score
100
September 24
14.9°C • 17% rain
Score
97
September 25
14.7°C • 20% rain
Score
95
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (September 21) in other destinations
Prague
Czech Republic
Paris
France
Rome
Italy
London
United Kingdom
Amsterdam
Netherlands
🌍 Explore the same date in different destinations around the world
📍 Is Stockholm Worth Visiting on September 21?
Planning a trip to Stockholm on September 21? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year is characterized by pleasant mild weather averaging 15.3°C with a 14% historical precipitation risk.
✈️ Travel Logistics: Approximately 318 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 7 vaccinations are recommended for Sweden, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 19°C (refreshing tonic). Wave conditions are generally lake-like with heights around 0.35m.
📊 Historical Extremes: The hottest September 21 recorded in the last 30 years saw temperatures hit 20.6°C in 2023, while the coldest dropped to 3.3°C in 2021.