August 20 is generally a great time to visit Boston. While there is a slight chance of rain (22%), showers are usually brief. Expect comfortable 26°C weather. Expect a bustling atmosphere in Boston right now—this is when the city truly comes alive with visitors.
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Essential Travel Info for Boston
Currency
USD
$ United States dollar
Language
English
Driving
Right side
Connect
Greater Boston uses10-digit dialing. Th...
Safety
Moderate Safety
GPI: 2.44
Boston Weather Forecast for August 20
"Warm & Sunny. Expect average highs of 26.4°C. 22% chance of rain."
What to Wear in Boston in August
Based on historical data for August 20, Boston typically experiences temperatures between 17.6°C and 26.4°C. We recommend packing t-shirt, light clothing to stay comfortable. Trends suggest it will stay mostly dry (22% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Boston
Smart Suitcase
- T-Shirt
- Light Clothing
Average High
26.4°C
Daytime Peak
Average Low
17.6°C
Nighttime Low
Feels Like
27.4°C
☀️ Minor difference
Rain Chance
22%
Avg 1.5mm if it rains
Cloud Cover
56%
Overcast
Pressure
1015.2 hPa
Medium volatility
Boston Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 83% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
04:00 - 09:30
16:00 - 18:00
Type I-II
🔴 20 min to burn
Type III-IV
🟡 30 min to burn
Type V-VI
🟢 50 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
21.2°C
Humid/Sticky
Heat Stress
Low
No heat warning
🙂 Best outdoor time:
Morning hours (before 11 AM)
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
⚠️ Mixed Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in United States
Flight Traffic
High
100/100 pressure index
Health Advisory
Healthy
Routine only • View Details →
Landing Slots
~676
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Boston
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
04:58
☀️ Noon
11:49
🌇 Sunset
18:40
⏱️ Daylight
13h 42m
Wind Speed
16.3 km/h
Gentle breeze
Sunshine
9.9 hrs
Direct Sun (Cloud-free)
Humidity
73%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Boston
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 Boston
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🔴 Very 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.
Atlantic Hurricane Risk
Season: Jun - Nov
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Boston on August 20 averages 26.4°C with a 22% precipitation probability. Wedding/Outdoor Event Score: 97/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Boston Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
August 25
26.5°C • 18% rain
Score
99
August 26
26.5°C • 16% rain
Score
99
August 23
26.3°C • 21% rain
Score
98
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (August 20) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Boston Worth Visiting on August 20?
Planning a trip to Boston on August 20? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year typically offers vibrant summer conditions averaging 26.4°C with a 22% historical precipitation risk.
✈️ Travel Logistics: Approximately 676 landing slots available daily during this period, indicating peak tourist activity.
🌊 Coastal Conditions: Water temperature averages 19.6°C (refreshing tonic). Wave conditions are generally lake-like with heights around 0.49m.
📊 Historical Extremes: The hottest August 20 recorded in the last 30 years saw temperatures hit 31.7°C in 2022, while the coldest dropped to 13.6°C in 2025.