Saint Helena
Satellite: Sentinel-2 cloudless 2016 by EOX (CC BY 4.0). Outline and points © OpenStreetMap contributors / Natural Earth. North up.
In numbers
0.057km²
Area
1km
Coastline
0
People
28°C
Warmest sea
April
1,536km
To the mainland
When to go to Boatswain Bird Island
Best for the beach from December to February, in June and in September.
The sea is warmest in April (28 °C) and coolest in September (24 °C). You can swim comfortably all year (21 °C or more).
Averages 1991–2020. Sea: NOAA OISST, the water within 35 km of the coast. Air, rain and sun: NASA POWER. Best months weigh warm afternoons (23–30 °C), sea of 24 °C or more and few wet days.
Island
Boatswain Bird Island is an island in Saint Helena. It covers 0.057 km², with 1 km of coastline. Nobody lives on it. The nearest mainland is 1,536 km away.
Getting there
- RAF Ascension Island (ASI)nearest airport with scheduled flights · 10 km in a straight line
- 1,536 km from the mainlanddistance to the nearest continental coast
- From December to February, June and Septemberbest months to go (from 30 years of averages)
Plan the trip
Ferries, stays and things to do
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The shape of the land.
On average the island stands 1 m above the sea. 100 % of it is below 200 m.
- 100 %0–50 m
Share of the island's area in each altitude band, from the Copernicus DEM (30 m, read at 30–240 m on large islands).
Size, for real
Next to islands you may know.
0.1 km
All outlines drawn to the same scale (Natural Earth and OpenStreetMap).
Month by month
The weather on the island.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon high (°C) | 26 | 27 | 28 | 28 | 27 | 26 | 25 | 24 | 24 | 24 | 24 | 25 |
| Night low (°C) | 25 | 26 | 27 | 27 | 26 | 26 | 25 | 24 | 24 | 24 | 24 | 24 |
| Sea (°C) | 26 | 27 | 28 | 28 | 28 | 27 | 26 | 25 | 24 | 24 | 25 | 25 |
| Rain (mm) | 4 | 4 | 10 | 12 | 8 | 5 | 6 | 5 | 4 | 6 | 5 | 3 |
| Wet days | 1 | 1 | 2 | 3 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 |
| Sun h/day | 9.5 | 9.7 | 9.7 | 9.2 | 9.1 | 8.8 | 8.4 | 7.5 | 7.1 | 6.8 | 7.2 | 8.3 |
| Wind (km/h) | 21 | 22 | 22 | 24 | 25 | 26 | 26 | 27 | 26 | 26 | 25 | 23 |
Averages 1991–2020 for the ~55 km NASA POWER cell over the island; the sea from NOAA OISST.
Recent years
Warmer and cooler years at sea.
Each month's sea temperature compared with its 1991–2020 average, in degrees.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2020 | +1.2 | +1.1 | +1.0 | +0.7 | +0.9 | +0.6 | +0.3 | ±0.0 | +0.1 | +0.4 | +0.1 | −0.1 |
| 2021 | −0.2 | −0.4 | −0.5 | +0.2 | ±0.0 | +0.5 | +0.9 | +1.2 | +1.2 | +1.2 | +0.5 | +0.1 |
| 2022 | +0.3 | +0.5 | +0.4 | +0.4 | +0.3 | +0.4 | +0.3 | +0.6 | +0.4 | +0.2 | ±0.0 | +0.1 |
| 2023 | +0.5 | +0.3 | +0.5 | +0.4 | +0.4 | +0.3 | +0.4 | +0.7 | +0.7 | +0.1 | +0.5 | +1.5 |
| 2024 | +1.3 | +1.4 | +1.5 | +1.5 | +1.0 | +0.7 | +0.2 | −0.1 | ±0.0 | ±0.0 | ±0.0 | +0.3 |
| 2025 | +0.5 | +0.7 | +0.3 | −0.3 | ±0.0 | +0.4 | +0.3 | +0.4 | +0.2 | +0.2 | +0.1 | −0.2 |
+1 warmer than usual −1 cooler than usual
Photos
Seen by visitors.
About these numbers
| Names, area, population | Wikidata (Q887601) · CC0 |
|---|---|
| Outline | © OpenStreetMap contributors · ODbL |
| Sea temperature | NOAA OISST v2.1 · 1991–2020 |
| Climate | NASA POWER · 1991–2020 |
| Relief, 3D model | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| Beaches, ports, lighthouses, trails | © OpenStreetMap contributors · ODbL |
| Towns | GeoNames · CC BY 4.0 |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
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