🇸🇭 Saint Helena, Ascension and Tristan da Cunha
National FlagGeography & Borders
This country has no land borders.
Introduction & Background
Saint Helena, Ascension and Tristan da Cunha4 is a British Overseas Territory located in the South Atlantic and consisting of the island of Saint Helena, Ascension Island and the archipelago of Tristan da Cunha including Gough Island. Its name was Saint Helena and Dependencies until 1 September 2009, when a new constitution came into force giving the three islands equal status as three territories, with a grouping under the Crown.
Of volcanic origin, the islands of Saint Helena, Ascension Island, and Tristan da Cunha were all formerly separate colonies of the English crown, though separately discovered by several Portuguese explorers between 1502 and 1504.
Geography & Climate
Climate, weather, and air quality data are based on historical records for the coordinates of the capital city, Jamestown.
Temperature (2025)
10°20°30°
Jan
22.2° / 23.3°
Feb
22.9° / 24.1°
Mar
23.2° / 24.5°
Apr
23° / 24.2°
May
22.2° / 23.2°
Jun
20.9° / 22.1°
Jul
19.8° / 21.2°
Aug
19.2° / 20.4°
Sep
19.4° / 20.3°
Oct
19.1° / 20.1°
Nov
19.5° / 20.5°
Dec
20.8° / 22°
Precipitation & Snow (2025)
Rain (mm) Snow (cm)
Atmospheric Pressure (2025)
1015-2.3Jan
1014-3.3Feb
1014.7-2.6Mar
1015-2.3Apr
1017.6+0.3May
1019.5+2.2Jun
1021.2+3.9Jul
1020.2+2.9Aug
1019+1.7Sep
1018.8+1.5Oct
1017.1-0.2Nov
1015.4-1.9Dec
Thunderstorm Days (2025)
0Jan
0Feb
0Mar
0Apr
0May
0Jun
0Jul
0Aug
0Sep
0Oct
0Nov
0Dec
Wind Speed (2025)
Air Quality — Monthly Averages (2025)
| Metric | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 μg/m³ | 9.1 | 10.3 | 8.7 | 8.6 | 8.7 | 9.8 | 9.2 | 8.9 | 14.4 | 12.1 | 10.1 | 9.5 |
| PM10 μg/m³ | 14.7 | 16.7 | 14.4 | 14.1 | 14.6 | 16.4 | 15.2 | 14.6 | 21.6 | 19.8 | 16.5 | 15.2 |
| O₃ μg/m³ | 44.5 | 48 | 49.5 | 61.7 | 64.1 | 74.3 | 78.4 | 77.5 | 81.7 | 73.9 | 66.3 | 51.8 |
| NO₂ μg/m³ | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| SO₂ μg/m³ | 0.2 | 0.2 | 0.2 | 0.1 | 0.1 | 0.2 | 0.1 | 0.1 | 0.1 | 0 | 0.1 | 0.1 |
| CO μg/m³ | 73 | 69 | 72 | 75 | 78 | 84 | 84 | 79 | 109 | 86 | 87 | 71 |
Pollen Levels — Monthly (2025)
Pollen data is negligible or unavailable for this location.
⛰️ Highest Elevation
Queen Mary's Peak on Tristan da Cunha2060 m / 6,759 ft
- Map Locations: Google Maps | OpenStreetMap
People & Society
Total Population5,651
Annual Growth RateN/AN/A
Life ExpectancyN/AAverage lifespan at birth
Fertility RateN/ABirths per woman