September 21 is generally a great time to visit Killarney. While there is a slight chance of rain (25%), showers are usually brief. Expect comfortable 17°C weather. Killarney is seeing high visitor numbers, so iconic spots may be busier than usual.
View the full calendar
Essential Travel Info for Killarney
Currency
EUR
€ Euro
Language
English
+1 more
Driving
Left side
Connect
As of May 2021, Killarney has 4G from al...
Safety
Very High Safety
GPI: 1.288
Killarney Weather Forecast for September 21
"Mild & Comfortable. Expect average highs of 16.5°C. 25% chance of rain."
What to Wear in Killarney in September
Based on historical data for September 21, Killarney typically experiences temperatures between 10.3°C and 16.5°C. We recommend packing light jacket, long pants to stay comfortable. Trends suggest it will stay mostly dry (25% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Killarney
Smart Suitcase
- Light Jacket
- Long Pants
Average High
16.5°C
Daytime Peak
Average Low
10.3°C
Nighttime Low
Feels Like
16.5°C
🌤️ Feels accurate
Rain Chance
25%
Avg 1.8mm if it rains
Cloud Cover
76%
Overcast
Pressure
1016 hPa
High volatility
Killarney Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 94% 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
13.8°C
Pleasant
Heat Stress
Low
No heat warning
🙂 Best outdoor time:
Any time during daylight hours
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Ireland
Flight Traffic
Busy
71/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~5
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Killarney
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
06:23
☀️ Noon
12:32
🌇 Sunset
18:41
⏱️ Daylight
12h 18m
Wind Speed
17.4 km/h
Gentle breeze
Sunshine
7.6 hrs
Direct Sun (Cloud-free)
Humidity
84%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Killarney
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 Killarney
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, Killarney on September 21 averages 16.5°C with a 25% precipitation probability. Wedding/Outdoor Event Score: 87/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Killarney Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
💡 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 Killarney Worth Visiting on September 21?
Planning a trip to Killarney 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 16.5°C with a 25% historical precipitation risk.
✈️ Travel Logistics: Approximately 5 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 6 vaccinations are recommended for Ireland, including COVID-19.
📊 Historical Extremes: The hottest September 21 recorded in the last 30 years saw temperatures hit 18.9°C in 2019, while the coldest dropped to 6.3°C in 2017.