Sudbury in Summer
In summer (June, July and August), Sudbury sees average daytime highs around 80°F and overnight lows near 62°F, with 10.1 in of rain over about 31 wet days across the season. It is the warmest season of the year and the driest season of the year.
Over the season highs climb from about 73°F in early June to 79°F by late August. The sky is clear or mostly clear about 27% of the time across summer, and the air most often feels dry.
Summer is Sudbury's best season of the year to visit on our travel score. For the whole year in context, see Sudbury's year-round climate.
- Avg daytime high
- 80°F
- warmest season of the year
- Avg overnight low
- 62°F
- Rainfall
- 10.1 in
- 31 wet days
- Avg wind
- 6 mph
- Travel score
- 6.3
- best season of the year
- Months
- Jun · Jul · Aug
Temperature in Sudbury in Summer
Over the season highs climb from about 73°F in early June to 79°F by late August.
A typical summer day in Sudbury reaches about 80°F and drops to 62°F overnight. The warmest of the three months is July, the coolest June.
How summer really feels in Sudbury
Once humidity and wind are folded in, summer brings about 0 days that feel above 90°F and 0 that feel at or below 32°F.
summer sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Sudbury weather by month
How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 35° / 20° | 3.2 | 9.6 | 6.2 | 9.3 | 0.0 |
| Feb | 37° / 22° | 3.0 | 8.5 | 5.7 | 10.3 | 0.0 |
| Mar | 45° / 29° | 4.1 | 11.1 | 5.1 | 11.6 | 1.1 |
| Apr | 57° / 39° | 3.6 | 10.5 | 1.2 | 13.1 | 4.0 |
| May | 67° / 49° | 3.1 | 10.5 | 0 | 14.4 | 6.0 |
| Jun | 77° / 58° | 3.5 | 10.7 | 0 | 15 | 6.5 |
| Jul | 83° / 64° | 3.2 | 10.3 | 0 | 14.8 | 5.8 |
| Aug | 81° / 62° | 3.4 | 9.6 | 0 | 13.7 | 6.5 |
| Sep | 73° / 55° | 3.4 | 8 | 0 | 12.3 | 7.0 |
| Oct | 61° / 44° | 3.7 | 9.3 | 0.2 | 10.8 | 5.3 |
| Nov | 50° / 34° | 3.3 | 9.1 | 1.1 | 9.6 | 2.3 |
| Dec | 40° / 26° | 4.1 | 10.3 | 5 | 9 | 0.1 |
Cloud cover in Summer
The sky is clear or mostly clear about 27% of the time across summer.
Chance of precipitation in Summer
Sudbury gets around 10.1 in of rain over 31 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 6 mph across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 54 min in early June to 13 h 06 min by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 5.6 kWh/m².
Hazard calendar for Sudbury
In summer, Sudbury overlaps its atlantic hurricane season. The full year is below, with each hazard's peak months called out.
Sudbury sits in the Atlantic hurricane belt; the season peaks August–October.
Is summer a good time to visit Sudbury?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit Sudbury for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Sudbury in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Sudbury sees daytime highs around 80°F and nights near 62°F. Pack light clothes. Worth having: rain gear and sun protection. About 31 days see rain.
Sea temperature near Sudbury in Summer
The nearest coast averages about 63°F across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 27 mi away) is warmest in August at about 66°F and coldest in February near 38°F.
The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 41 | 38 | 38 | 42 | 50 | 58 | 65 | 66 | 63 | 56 | 50 | 46 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Cool | Cool | Cool | Bracing | Bracing | Bracing |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 41 | Bracing |
| Feb | 38 | Bracing |
| Mar | 38 | Bracing |
| Apr | 42 | Bracing |
| May | 50 | Bracing |
| Jun | 58 | Bracing |
| Jul | 65 | Cool |
| Aug | 66 | Cool |
| Sep | 63 | Cool |
| Oct | 56 | Bracing |
| Nov | 50 | Bracing |
| Dec | 46 | Bracing |
UV index in Sudbury in Summer
Clear-sky midday UV across summer averages around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Sudbury peaks around July 10 at about 7 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 23 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 3 | 4 | 5 | 7 | 7 | 7 | 5 | 6 | 3 | 2 | 1 |
| Level | Low | Moderate | Moderate | High | Very high | Very high | Very high | Moderate | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 3 | Moderate |
| Mar | 4 | Moderate |
| Apr | 5 | High |
| May | 7 | Very high |
| Jun | 7 | Very high |
| Jul | 7 | Very high |
| Aug | 5 | Moderate |
| Sep | 6 | High |
| Oct | 3 | Moderate |
| Nov | 2 | Moderate |
| Dec | 1 | Low |
Air quality in Sudbury in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Sudbury is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (November, 8 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 9 | 13 | 13 | 13 | 14 | 13 | 16 | 14 | 11 | 9 | 8 | 9 |
| Level | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 9 | Good |
| Feb | 13 | Moderate |
| Mar | 13 | Moderate |
| Apr | 13 | Moderate |
| May | 14 | Moderate |
| Jun | 13 | Moderate |
| Jul | 16 | Moderate |
| Aug | 14 | Moderate |
| Sep | 11 | Good |
| Oct | 9 | Good |
| Nov | 8 | Good |
| Dec | 9 | Good |
Where is Sudbury?
Sudbury sits at 42.4°N, 71.4°W, 184 ft above sea level, in United States. The nearest listed city is Framingham Center, 6.2 mi away.
Topography around Sudbury
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Sudbury.
Within 2 miles, the terrain around Sudbury has only modest variations in elevation — a maximum elevation change of 344 ft around an average of 194 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 600 ft; within 50 miles, large variations in elevation — a maximum elevation change of 3,176 ft.
The land around Sudbury is covered by trees (85%) within 2 miles, trees (82%) within 10 miles, and trees (76%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Sudbury (42.3834°, -71.4162°, elevation 184 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.