United StatesIsland

Umnak

1,768 km² rising to 2,149 m out of the Bering Sea.

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

In numbers

1,768km²

Area

424km

Coastline

2,149m

Highest point

Mount Vsevidof

People

10°C

Warmest sea

August

324km

To the mainland

When to go to Umnak

Good all year round.

The sea is warmest in August (10 °C) and coolest in February (4 °C). The water never reaches 21 °C: bring a wetsuit.

4°2°1°

Jan21

4°3°1°

Feb20

4°2°1°

Mar20

4°4°2°

Apr18

5°5°4°

May17

7°8°6°

Jun15

8°10°8°

Jul19

10°11°10°

Aug19

9°10°8°

Sep19

8°7°6°

Oct22

6°5°4°

Nov21

5°4°2°

Dec23

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

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 in Aleutians West Census Area, Alaska, United States

Umnak is an island in United States. It covers 1,768 km², with 424 km of coastline. Its highest point, Mount Vsevidof, rises to 2,149 m. About 39 people live on it. The nearest mainland is 324 km away.

Getting there

Tom Madsen (Dutch Harbor) Airport (DUT)nearest airport with scheduled flights · 145 km in a straight lineCar hire at ANC airport (Anchorage)Discover Cars · Affiliate link
324 km from the mainlanddistance to the nearest continental coast

Plan the trip

Ferries, stays and things to do

Car hire at ANC airport (Anchorage)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.

On the island

What you find on Umnak.

1beaches
4named peaksJag Peak, Mount Idak, Ikaagux and 1 more
5volcanoesMount Vsevidof, Mount Okmok, Tulik Volcano and 2 more
1castles and forts
1ruins and archaeological sitesOld Cabin
1hotels, guesthouses and apartments

Counted in OpenStreetMap, the map anyone can edit, inside the island's outline. A low number may only mean nobody has mapped it yet.

Cross-checked with our atlases

Umnak in our other atlases

Everything Coastya, Peakyas, Lakeyas and Cascadyas know about what lies inside Umnak, each with its own numbers.

3beaches and covesCoastya
10mountainsPeakyas
4lakesLakeyas

Highest point
2,149m
Mount Vsevidof
prominence 2,149 m · according to Peakyas
Largest lake
0.57km²
Kicham Anii
according to Lakeyas
Beach with the warmest sea
9.8°C
Utunan
sea in the warmest month · according to Coastya

3 beaches

on Coastya, the beach atlas

Utunan9.8°C
Asudakix Sitxa9.6°C
Qigunam-tugumaga9.2°C

Open Coastya ↗

10 mountains

on Peakyas, the mountain atlas

Mount Vsevidofprominence 2,149 m2,149m
Mount Recheshnoi1,984m
Mount Okmok1,073m
Elbow Hill
High Hill
Ikaagux
Jag Peak
Teapot Hill

2 more on PeakyasOpen Peakyas ↗

4 lakes

on Lakeyas, the lake atlas

Kicham Anii0.57km²
Alim Anii0.45km²
Ugluudam Anii0.20km²
Algiinam Anii0.12km²

Lakeyas is coming soonOpen Lakeyas ↗

The shape of the land.

On average the island stands 281 m above the sea. 52 % of it is below 200 m.

18 %0–50 m
34 %50–200 m
29 %200–500 m
16 %500–1,000 m
2 %1,000–2,000 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.

Umnak1,768 km²

Tenerife2,038 km²

Long Island3,529 km²

50 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)	2	3	2	4	5	8	10	11	10	7	5	4
Night low (°C)	1	1	1	2	4	6	8	10	8	6	4	2
Sea (°C)	4	4	4	4	5	7	8	10	9	8	6	5
Rain (mm)	111	112	84	79	91	91	107	106	110	132	112	154
Wet days	21	20	20	18	17	15	19	19	19	22	21	23
Sun h/day	0.9	1.7	3.2	4.0	3.9	3.6	2.8	2.6	3.1	2.8	1.4	0.6
Wind (km/h)	33	33	31	31	24	21	20	22	28	32	34	34

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	+0.4	+0.4	±0.0	+0.3	+0.6	+0.8	+1.5	+0.3	+0.3	+0.4	+0.5	+0.2
2021	+0.2	+0.8	+0.3	+0.6	+0.4	+0.2	+0.4	+1.1	+1.0	−0.5	−0.8	−0.4
2022	−0.2	−0.1	−0.2	−0.3	+0.1	−0.3	−1.3	−1.7	−0.9	−0.4	−0.2	+0.4
2023	+0.4	+0.6	+0.1	+0.2	−0.3	−0.3	−1.2	−1.0	−0.7	±0.0	+0.8	+0.4
2024	+0.3	+0.2	−0.1	±0.0	−0.4	−0.7	−0.8	−1.5	−1.4	−0.7	−0.2	+0.2
2025	+0.7	+0.8	+0.6	+0.5	+0.4	−0.1	−0.4	−0.2	−0.2	+0.2	+0.3	+0.5

+1 warmer than usual −1 cooler than usual

Photos

Seen by visitors.

Umnak and Unalaska Islands — Bigwumpus · CC BY-SA 4.0

Nearby

More islands nearby.

Unalaska Island

United States2,701 km²1,800 m128 km away

Akutan Island

United States330 km²1,255 m194 km away

Unimak Island

United States4,119 km²2,857 m326 km away

About these numbers

Names, area, population	Wikidata (Q264718) · 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
Beaches, mountains, lakes and waterfalls	Coastya, Peakyas, Lakeyas — Wikidata · CC0; © OpenStreetMap contributors · ODbL; GeoNames · CC BY 4.0; NOAA OISST; HydroLAKES (Messager et al. 2016) · CC BY 4.0, LakeTEMP (Korver et al. 2024) · CC BY 4.0

Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.

The family

Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers or canyons?

Same idea, other landscapes: field atlases built on open data, month by month, in seven languages.

beaches

Find your beach: sea temperature, sun and swimming month by month.Visit

lakes

Every lake on Earth: water temperature, ice, depth and the shore.Coming soonVisit

mountains

Every summit in 3D: summit weather, the 0 °C line, huts and trails.Visit

waterfalls Cascadyas

Every waterfall: height, flow month by month and when it roars.Coming soonVisit

islands

Every island from the sea up: size, sea temperature, ferries and 3D.You are here

rivers

Every river from source to sea: the journey, the flow and the basin in numbers.Visit

canyons

Every canyon cut to scale: depth to the floor, rim and floor temperatures, trails and viewpoints.Visit