October 21 is generally a great time to visit London. While there is a slight chance of rain (37%), showers are usually brief. Expect comfortable 15°C weather. Expect a bustling atmosphere in London right now—this is when the city truly comes alive with visitors.
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Essential Travel Info for London
Currency
GBP
£ British pound
Language
English
Driving
Left side
Connect
London is unfortunately not noted for fr...
Safety
High Safety
GPI: 1.667
London Weather Forecast for October 21
"Mild & Comfortable. Expect average highs of 14.5°C. 37% chance of rain."
What to Wear in London in October
Based on historical data for October 21, London typically experiences temperatures between 8.3°C and 14.5°C. We recommend packing light jacket, long pants, umbrella to stay comfortable. With a 37% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for London
Smart Suitcase
- Light Jacket
- Long Pants
- Umbrella
Average High
14.5°C
Daytime Peak
Average Low
8.3°C
Nighttime Low
Feels Like
14.3°C
🌤️ Feels accurate
Rain Chance
37%
Avg 2mm if it rains
Cloud Cover
70%
Overcast
Pressure
1009.7 hPa
High volatility
London Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 90% 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
🔴 80 min to burn
Type III-IV
🟡 120 min to burn
Type V-VI
🟢 200 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
11.8°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 United Kingdom
Flight Traffic
High
100/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~2,634
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in London
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
06:35
☀️ Noon
11:46
🌇 Sunset
16:57
⏱️ Daylight
10h 21m
Wind Speed
21.4 km/h
Moderate wind
Sunshine
5.3 hrs
Direct Sun (Cloud-free)
Humidity
84%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for London
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 London
Travel Comfort Index
Real-time tourism conditions
Weather Quality
⛅ Good
Tourist Crowds
🟡 Busy
Price Level
💰💰 Moderate
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
Rare minor tremors. Buildings are earthquake-resistant.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, London on October 21 averages 14.5°C with a 37% precipitation probability. Wedding/Outdoor Event Score: 84/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
London Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
October 15
14.8°C • 19% rain
Score
92
October 17
14.9°C • 28% rain
Score
92
October 16
14.9°C • 23% rain
Score
91
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (October 21) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is London Worth Visiting on October 21?
Planning a trip to London on October 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 14.5°C with a 37% historical precipitation risk.
✈️ Travel Logistics: Approximately 2,634 landing slots available daily during this period, indicating peak tourist activity.
💉 Health Advisory: 8 vaccinations are recommended for United Kingdom, including COVID-19.
📊 Historical Extremes: The hottest October 21 recorded in the last 30 years saw temperatures hit 17.7°C in 2022, while the coldest dropped to 5°C in 2021.