United StatesAtoll

Johnston Atoll

2.5 km² of land in the Pacific Ocean.

N 0.5 km

Satellite: Sentinel-2 cloudless 2016 by EOX (CC BY 4.0). Outline and points © OpenStreetMap contributors / Natural Earth. North up.

In numbers

2.5km²

Area

9km

Coastline

10m

Highest point

Sand Island

People

28°C

Warmest sea

September

4,262km

To the mainland

When to go to Johnston Atoll

Best for the beach from January to February and from May to July.

The sea is warmest in September (28 °C) and coolest in March (25 °C). You can swim comfortably all year (21 °C or more).

26°26°25°

Jan3

26°25°25°

Feb5

25°25°25°

Mar10

26°26°25°

Apr7

26°26°26°

May6

27°27°26°

Jun4

27°27°26°

Jul6

28°27°27°

Aug11

28°28°27°

Sep11

28°27°27°

Oct15

27°27°26°

Nov12

26°26°26°

Dec7

Sea temperature (the water level) Air: night low to afternoon high Wet days Best months

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.

Unincorporated territory of the United States

Johnston Atoll is an atoll in United States. It covers 2.5 km², with 9 km of coastline. Its highest point, Sand Island, rises to 10 m. Nobody lives on it. The nearest mainland is 4,262 km away.

Getting there

4,262 km from the mainlanddistance to the nearest continental coast
From January to February and from May to Julybest months to go (from 30 years of averages)

Plan the trip

Ferries, stays and things to do

Car hire at LIH airport (Lihue, Kauai)Discover CarsSee

Some links above are affiliate links: if you book through them we may earn a commission, at no extra cost to you. It never changes what the data on this page says.

The shape of the land.

On average the island stands 4 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.

Johnston Atoll3 km²

Capri10 km²

2 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	25	25	26	26	27	27	27	28	27	27	26
Night low (°C)	25	25	25	25	26	26	26	27	27	27	26	26
Sea (°C)	26	26	25	26	26	27	27	28	28	28	27	26
Rain (mm)	9	31	64	31	29	16	27	48	48	76	59	46
Wet days	3	5	10	7	6	4	6	11	11	15	12	7
Sun h/day	8.7	8.7	8.5	9.4	9.8	10.1	10.0	9.5	9.1	8.1	7.7	7.9
Wind (km/h)	25	27	27	27	25	26	26	25	24	24	27	27

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	+0.7	+0.4	+0.2	+0.4	+0.4	+0.3	+0.6	+0.6	+0.5	+0.2	+0.5	+0.6
2021	+0.6	+0.7	+0.5	+0.2	+0.2	+0.2	+0.4	+0.5	+0.3	+0.1	−0.1	+0.3
2022	+0.8	+0.8	+0.6	+0.5	+0.6	+0.4	±0.0	+0.1	+0.2	+0.4	+0.3	+0.3
2023	+0.7	+0.3	+0.7	+0.9	+0.9	+0.5	+0.5	+0.1	±0.0	+0.1	+0.3	+0.6
2024	+0.8	+0.6	+0.6	+0.2	+0.5	+0.7	+0.4	+0.3	+0.4	+0.3	+0.3	+0.3
2025	+0.5	+0.6	+0.7	+1.1	+1.0	+0.6	+0.4	±0.0	+0.2	+0.4	+0.2	+0.4

+1 warmer than usual −1 cooler than usual

Photos

Seen by visitors.

Sunset at Johnston Atoll (8428209506) — USFWS - Pacific Region · Public domain

Sooty terns on flight at Johnston Atoll NWR — Eric Baker · Public domain

Johnston Atoll Chemical Agent Disposal System Nov 1990 — SSgt. Val Gempis, USAF · Public domain

Get Your Goose On! Atoll Style (8047992997) — USFWS Mountain-Prairie · Public domain

About these numbers

Names, area, population	Wikidata (Q131008) · 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