St. John's in Summer
In summer (June, July and August), St. John's sees average daytime highs around 28°C and overnight lows near 26°C, with 227 mm of rain over about 46 wet days across the season. It is the warmest season of the year and the 2nd-wettest season.
Across summer, daytime highs hold fairly steady around 28°C. The sky is clear or mostly clear about 49% of the time across summer, and the air most often feels oppressive.
Summer is St. John's's 3rd-best season to visit on our travel score. St. John's has little temperature swing across the year, so its calendar seasons blur — the season framing matters less here than for a place with four distinct seasons. For the whole year in context, see St. John's's year-round climate.
- Avg daytime high
- 28°C
- warmest season of the year
- Avg overnight low
- 26°C
- Rainfall
- 227 mm
- 46 wet days
- Avg wind
- 27 km/h
- Travel score
- 5.8
- 3rd-best season
- Months
- Jun · Jul · Aug
Temperature in St. John's in Summer
Across summer, daytime highs hold fairly steady around 28°C.
A typical summer day in St. John's reaches about 28°C and drops to 26°C overnight. The warmest of the three months is August, the coolest June.
How summer really feels in St. John's
Once humidity and wind are folded in, summer brings about 16 days that feel above 32°C and 0 that feel at or below 0°C.
The story in summer is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
St. John's 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 (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 26° / 24° | 32 | 10 | 11.1 | 7.3 |
| Feb | 25° / 24° | 21 | 7.1 | 11.4 | 7.7 |
| Mar | 25° / 24° | 21 | 6.6 | 11.9 | 7.8 |
| Apr | 26° / 25° | 33 | 8.8 | 12.4 | 7.2 |
| May | 27° / 26° | 62 | 12.4 | 12.8 | 6.3 |
| Jun | 27° / 26° | 51 | 12.1 | 13 | 6.1 |
| Jul | 28° / 26° | 78 | 15.9 | 12.9 | 5.8 |
| Aug | 28° / 26° | 98 | 17.8 | 12.6 | 5.4 |
| Sep | 28° / 26° | 127 | 18 | 12.1 | 4.9 |
| Oct | 28° / 26° | 132 | 18.8 | 11.6 | 5.2 |
| Nov | 27° / 26° | 103 | 15.8 | 11.2 | 5.8 |
| Dec | 26° / 25° | 58 | 13.3 | 11 | 6.6 |
Cloud cover in Summer
The sky is clear or mostly clear about 49% of the time across summer.
Chance of precipitation in Summer
St. John's gets around 227 mm of rain over 46 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 27 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 12 h 54 min in early June to 12 h 24 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 6.5 kWh/m².
Hazard calendar for St. John's
In summer, St. John's overlaps its atlantic hurricane, rainy season and dust season. The full year is below, with each hazard's peak months called out.
St. John's sits in the Atlantic hurricane belt; the season peaks August–October.
St. John's's rainy season runs July–November, when most of the year's rain falls.
St. John's sees seasonal dust haze (July), heaviest in July.
Is summer a good time to visit St. John's?
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 St. John's for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for St. John's in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, St. John's sees daytime highs around 28°C and nights near 26°C. Pack light clothes, rain gear, sun protection and a windbreaker. About 46 days see rain.
Sea temperature near St. John's in Summer
The nearest coast averages about 28°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea offshore is warmest in September at about 29°C and coldest in February near 26°C.
The water stays above 20°C all year — warm enough for a swim any month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 27 | 26 | 26 | 27 | 27 | 28 | 28 | 29 | 29 | 29 | 28 | 27 |
| Comfort | Warm | Warm | Warm | Warm | Warm | Warm | Tropical | Tropical | Tropical | Tropical | Tropical | Warm |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 27 | Warm |
| Feb | 26 | Warm |
| Mar | 26 | Warm |
| Apr | 27 | Warm |
| May | 27 | Warm |
| Jun | 28 | Warm |
| Jul | 28 | Tropical |
| Aug | 29 | Tropical |
| Sep | 29 | Tropical |
| Oct | 29 | Tropical |
| Nov | 28 | Tropical |
| Dec | 27 | Warm |
UV index in St. John's in Summer
Clear-sky midday UV across summer averages around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in St. John's peaks around April 10 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 7 (very high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 8 | 11 | 13 | 13 | 12 | 12 | 12 | 11 | 12 | 10 | 8 | 7 |
| Level | Very high | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | Very high |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 8 | Very high |
| Feb | 11 | Extreme |
| Mar | 13 | Extreme |
| Apr | 13 | Extreme |
| May | 12 | Extreme |
| Jun | 12 | Extreme |
| Jul | 12 | Extreme |
| Aug | 11 | Extreme |
| Sep | 12 | Extreme |
| Oct | 10 | Extreme |
| Nov | 8 | Very high |
| Dec | 7 | Very high |
Air quality in St. John's 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 St. John's is worst in July — around 24 µg/m³ PM2.5 (moderate), about 3.2× the cleanest month (December, 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) | 8 | 10 | 9 | 11 | 14 | 24 | 24 | 20 | 16 | 17 | 11 | 8 |
| Level | Good | Good | Good | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 8 | Good |
| Feb | 10 | Good |
| Mar | 9 | Good |
| Apr | 11 | Good |
| May | 14 | Moderate |
| Jun | 24 | Moderate |
| Jul | 24 | Moderate |
| Aug | 20 | Moderate |
| Sep | 16 | Moderate |
| Oct | 17 | Moderate |
| Nov | 11 | Good |
| Dec | 8 | Good |
Where is St. John's?
St. John's sits at 17.1°N, 61.8°W, 12 m above sea level, in Antigua and Barbuda. The nearest listed city is Falmouth, 12 km away.
Topography around St. John's
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of St. John's.
Within 3 km, the terrain around St. John's has only modest variations in elevation — a maximum elevation change of 109 m around an average of 20 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 391 m; within 80 km, large variations in elevation — a maximum elevation change of 1,011 m.
The land around St. John's is covered by artificial surfaces (35%) and trees (31%) within 3 km, water (69%) within 16 km, and water (96%) within 80 km.
Antigua and Barbuda travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type A / B
- 230 V · 60 Hz
- Prices
- ≈ 69% of US
- price level, 2025
- GDP per capita
- $24,819
- 2025
- Homicide rate
- 10.7
- per 100k, 2023
- Road deaths
- 0
- 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 St. John's (17.121°, -61.8433°, elevation 12 m), 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.