September 21 sees frequent showers in Reykjavik. Historical data shows a 50% chance of rain, so pack accordingly. Temperatures average 10°C. Lower tourist interest in Reykjavik right now translates to better deals and a more local feel.
View the full calendar
Essential Travel Info for Reykjavik
Currency
ISK
kr Icelandic króna
Language
Icelandic
Driving
Right side
Safety
Very High Safety
GPI: 1.107
Reykjavik Weather Forecast for September 21
"Mild & Comfortable. Expect average highs of 9.9°C. 50% chance of rain."
What to Wear in Reykjavik in September
Based on historical data for September 21, Reykjavik typically experiences temperatures between 5.3°C and 9.9°C. We recommend packing heavy coat, scarf, gloves along with other layers to stay comfortable. With a 50% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for Reykjavik
Smart Suitcase
- Heavy Coat
- Scarf
- Gloves
- Umbrella
Average High
9.9°C
Daytime Peak
Average Low
5.3°C
Nighttime Low
Feels Like
7°C
❄️ Slightly colder
Rain Chance
50%
Avg 3.6mm if it rains
Cloud Cover
78%
Moderate drizzle
Pressure
1006.3 hPa
High volatility
Reykjavik Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 93% 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
🔴 67 min to burn
Type III-IV
🟡 101 min to burn
Type V-VI
🟢 168 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
7.5°C
Dry air
Heat Stress
Low
No heat warning
😕 Best outdoor time:
Midday (11 AM - 3 PM) when warmest
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 Iceland
Flight Traffic
Quiet
39/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~43
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Reykjavik
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
07:08
☀️ Noon
13:22
🌇 Sunset
19:36
⏱️ Daylight
12h 27m
Wind Speed
22.7 km/h
Moderate wind
Sunshine
5.3 hrs
Direct Sun (Cloud-free)
Humidity
85%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Reykjavik
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 Reykjavik
Travel Comfort Index
Real-time tourism conditions
Weather Quality
⛅ Good
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Rapid pressure changes detected. High risk for meteosensitive people.
Low pressure & humidity may aggravate joints.
Fish are active due to pressure changes.
Air quality is excellent. Perfect for outdoor activities.
Regional Safety Profile
Seismic Activity
Active seismic zone. Multiple earthquakes per year.
Travel Alert: This region has elevated natural risks. We recommend registering with your embassy and keeping emergency numbers handy.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Reykjavik on September 21 averages 9.9°C with a 50% precipitation probability. Wedding/Outdoor Event Score: 52/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Reykjavik Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
September 14
10.9°C • 40% rain
Score
60
September 15
10.8°C • 40% rain
Score
59
September 16
10.6°C • 46% rain
Score
56
💡 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 Reykjavik Worth Visiting on September 21?
Planning a trip to Reykjavik on September 21? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year offers a bracing seasonal atmosphere averaging 9.9°C with a 50% historical precipitation risk.
✈️ Travel Logistics: Approximately 43 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 6 vaccinations are recommended for Iceland, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 10.2°C (polar plunge). Wave conditions are generally fun waves with heights around 0.91m.
📊 Historical Extremes: The hottest September 21 recorded in the last 30 years saw temperatures hit 14°C in 2019, while the coldest dropped to 0.8°C in 2023.