United States Boston Weather in August — Climate Guide
August in Boston is very-high
August is very-high for Boston.
August is Boston's second-hottest month — 27°C / 81°F days, 18°C / 64°F nights, 70% humidity (the most-humid month of the year). Afternoon thunderstorm risk peak. Boston Harborwalk + Esplanade morning walks ideal before afternoon humidity.
North End Italian feasts continue — Fisherman's Feast (mid-August, since 1910, the largest North End feast) + Saint Agrippina di Mineo Feast (early August). Free street festivals with Italian processions + music + Italian-American food.
Travel score
Boston August Weather Stats
Avg High
27°C
Avg Low
18°C
Rainy Days
9
90mm total
Sunshine
10h
Daily avg
Humidity
70%
humid
UV Index
9
Very high
Wind
11 km/h
Gusts 28
Sea Temp
22°C
swimming
Crowds
Very busy
At attractions
August Sunrise & Sunset
Air Quality
PM2.5
10 μg/m³
PM10
22 μg/m³
Status
good
Feels-Like Temperature & Wind
Feels like
Daytime
31°C
Nighttime
19°C
Humidity and wind affect how the actual temperature feels.
Wind
11 km/h
Max gust 28 km/h
Activities Recommended for August
August Travel Pros & Cons
Pros
- Italian feasts North End peak
- Long summer daylight
- Fenway Park Red Sox All-Star break ending
- University-tour family season peak
- Sea temperature warm enough for Cape Cod swimming
Cons
- Hottest most-humid month (70% humidity)
- Afternoon thunderstorm peak
- Hurricane season starting
- Hotels at sustained peak
August Events & Festivals
- Italian Fisherman's Feast North End (mid-August)
- Saint Agrippina di Mineo Feast (early August)
- Korean Lunar New Year (varies)
- Massachusetts pre-Labor Day school prep
Boston in August — Full Picture
August is Boston's second-hottest month — 27°C / 81°F days, 18°C / 64°F nights, 70% humidity (the most-humid month of the year). Afternoon thunderstorm risk peak. Boston Harborwalk + Esplanade morning walks ideal before afternoon humidity.
North End Italian feasts continue — Fisherman's Feast (mid-August, since 1910, the largest North End feast) + Saint Agrippina di Mineo Feast (early August). Free street festivals with Italian processions + music + Italian-American food.
US summer school break ending — Massachusetts public schools start late August (the last week of summer school vacation). Korean summer school break also ending — Korean tourist surge to Boston includes university-tour families.
Hotels at sustained peak — book 4-6 months ahead for August dates. Marathon weekend already booked solid.
Weather caution: afternoon thunderstorms peak, with occasional severe weather warnings. Hurricane season risk (the rare New England hurricane historically Sept-Oct). Pack umbrella + light rain jacket. Hydration essential.
The smart August move: target the last week (Massachusetts back-to-school transition, US schools resume) for slight pricing drop before Labor Day weekend rebound.
What to Wear & What to Pack
Late summer hot + humid — light cotton t-shirt + shorts + sandals. Sunscreen SPF 30+. AC light layer. Afternoon thunderstorms peak.
Packing Checklist
Seasonal Weather Overview
Spring (Mar·Apr·May)
14°C
4.3°C
11.7/mo
Summer (Jun·Jul·Aug)
Current26.7°C
17.3°C
9.7/mo
Autumn (Sep·Oct·Nov)
17°C
8.3°C
9.7/mo
Winter (Dec·Jan·Feb)
3.7°C
-4.7°C
11/mo
Boston Monthly Weather Comparison
| Month | High | Low | Rain | Sun | Humid | UV | Crowd | Price |
|---|---|---|---|---|---|---|---|---|
| 2° | -6° | 11d·90mm | 5h | 65% | 2 | Quiet | Low season | |
| 4° | -5° | 10d·80mm | 6h | 64% | 3 | Quiet | Low season | |
| 8° | -1° | 12d·95mm | 7h | 62% | 4 | Quiet | Low season | |
| 14° | 4° | 12d·95mm | 8h | 60% | 5 | Very busy | Peak | |
| May (Best) | 20° | 10° | 11d·90mm | 9h | 60% | 7 | Very busy | Peak |
| June (Best) | 25° | 15° | 11d·90mm | 10h | 64% | 9 | Busy | Peak |
| July (Best) | 28° | 19° | 9d·85mm | 11h | 67% | 10 | Very busy | Peak |
| August (Best) | 27° | 18° | 9d·90mm | 10h | 70% | 9 | Very busy | Peak |
| September (Best) | 23° | 14° | 9d·90mm | 9h | 65% | 7 | Very busy | Peak |
| October (Best) | 17° | 8° | 9d·95mm | 7h | 65% | 5 | Very busy | Peak |
| 11° | 3° | 11d·95mm | 5h | 65% | 3 | Busy | Peak | |
| 5° | -3° | 12d·100mm | 5h | 65% | 2 | Very busy | Peak |
View Other Months
Boston August Hotel Picks
Frequently Asked Questions
Is August a good time to visit Boston?
Boston in August is very-high. Tourist crowds are very busy and flight/hotel prices are peak.
What's the average temperature in Boston in August?
Boston August averages a high of 27°C and a low of 18°C.
Does it rain much in Boston in August?
Boston August averages 90mm of rainfall over about 9 rainy days.
What should I wear in Boston in August?
Late summer hot + humid — light cotton t-shirt + shorts + sandals. Sunscreen SPF 30+. AC light layer. Afternoon thunderstorms peak.
What time are sunrise and sunset in Boston in August?
Boston August sunrise is 05:45 and sunset is 19:45, with 14h 0m of daylight.
What's the air quality like in Boston in August?
Boston August air quality (AQI) averages 35, rated Good. PM2.5 averages 10μg/m³.
What activities are recommended in Boston in August?
In August, Boston is great for North End Italian feasts (Fisherman's, Saint Agrippina), Boston Harborwalk morning walks, Fenway Park Red Sox.
Is August peak season in Boston?
Boston August crowds are very busy and prices are peak. Advance reservations are strongly recommended.
Best Months to Visit Boston
View Other Months
Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.