August 9 is generally a great time to visit Boston. While there is a slight chance of rain (30%), showers are usually brief. Expect comfortable 28°C weather. As it's peak season for Boston, we recommend booking your stay well in advance to secure the best rates.
View the full calendar
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 9
"Warm & Sunny. Expect average highs of 27.8°C. 30% chance of rain."
What to Wear in Boston in August
Based on historical data for August 9, Boston typically experiences temperatures between 18.7°C and 27.8°C. We recommend packing t-shirt, light clothing to stay comfortable. With a 30% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for Boston
Smart Suitcase
- T-Shirt
- Light Clothing
Average High
27.8°C
Daytime Peak
Average Low
18.7°C
Nighttime Low
Feels Like
30.5°C
🔥 Feels warmer
Rain Chance
30%
Avg 1.9mm if it rains
Cloud Cover
53%
Overcast
Pressure
1014.9 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 78% 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
🔴 19 min to burn
Type III-IV
🟡 29 min to burn
Type V-VI
🟢 48 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
22.3°C
Humid/Sticky
Heat Index
30.5°C
Feels hotter
😐 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
04:46
☀️ Noon
11:51
🌇 Sunset
18:55
⏱️ Daylight
14h 9m
Wind Speed
16.8 km/h
Gentle breeze
Sunshine
10.6 hrs
Direct Sun (Cloud-free)
Humidity
72%
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
⛅ Good
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 9 averages 27.8°C with a 30% precipitation probability. Wedding/Outdoor Event Score: 95/100."
— 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 2
28.2°C • 22% rain
Score
97
August 4
28.3°C • 23% rain
Score
97
August 5
28.1°C • 24% rain
Score
97
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (August 9) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Boston Worth Visiting on August 9?
Planning a trip to Boston on August 9? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year typically offers vibrant summer conditions averaging 27.8°C with a 30% historical precipitation risk.
✈️ Travel Logistics: Approximately 676 landing slots available daily during this period, indicating peak tourist activity.
🌊 Coastal Conditions: Water temperature averages 19.2°C (refreshing tonic). Wave conditions are generally lake-like with heights around 0.44m.
📊 Historical Extremes: The hottest August 9 recorded in the last 30 years saw temperatures hit 36°C in 2022, while the coldest dropped to 15.2°C in 2017.