Historical tsunamis · Oct 19, 2020, 8:54 PM UTC

2020 Shumagin Islands, Ak tsunami

United States

The tsunami of Oct 19, 2020, 8:54 PM UTC originated near Shumagin Islands, Ak (United States).

Key facts

Date
Oct 19, 2020, 8:54 PM UTC
Cause
Earthquake
Magnitude
M7.6
Depth
28 km
Maximum documented water height
0.76 m
Observation records
33
Countries affected
2

It was triggered by a magnitude 7.6 earthquake at a depth of 28 km.

The highest documented water height was 0.76 m (Chignik, Ak, United States).

33 observation sites in 2 countries are recorded.

Outside the source country, the earliest documented arrival was at Henslung Cove, British Columbia (Canada) after 2:18 h.

All tsunamis in United StatesRecord at NOAA/NCEI ↗

Map of observation sites

33

Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.

Tsunami arrival times

Documented arrival times from the NOAA/NCEI database, showing the earliest recorded location per country. Coverage is incomplete: a country without an entry was not necessarily spared.

  1. 0:00 hEarthquake (origin) · Oct 19, 2020, 8:54 PM UTC
  2. 2:15 hUnited States · Sand Point, Ak · 0.70 m
  3. 2:18 hCanada · Henslung Cove, British Columbia · 0.06 m

16 places with a documented arrival time

Observations by country

CountryObservation recordsMaximum documented water heightDeathsEarliest arrival
United States170.76 m
Chignik, Ak		—2:15 h
Canada160.08 m
Port Renfrew, British Columbia		—2:18 h

Highest documented water heights

15 / 33

Individual documented observations for this event. Heights come from different measurement types and sources; not every location has a measured height.

Location / stationObserved heightDistance from sourceCountry
Chignik, Ak · Ak0.76 m206 kmUnited States
Sand Point, Ak · Ak0.70 m99 kmUnited States
King Cove, Ak · Ak0.64 m181 kmUnited States
Hilo, Hawaii, Hi · Hi0.28 m3,890 kmUnited States
Hanalei, Kauai, Hi · Hi0.26 m3,596 kmUnited States
Crescent City, Ca · Ca0.21 m2,955 kmUnited States
Haleiwa, Oahu, Hi · Hi0.19 m3,666 kmUnited States
Kahului, Maui, Hi · Hi0.13 m3,751 kmUnited States
Nawiliwili, Kauai, Hi · Hi0.09 m3,624 kmUnited States
Nikolski, Ak · Ak0.09 m636 kmUnited States
Unalaska, Dutch Harbor, Ak · Ak0.09 m457 kmUnited States
Port Renfrew, British Columbia · Bc0.08 m2,503 kmCanada
Ucluelet, British Columbia · Bc0.08 m2,408 kmCanada
Winter Harbor, British Columbia · Bc0.08 m2,171 kmCanada
Port Alberni, British Columbia · Bc0.07 m2,441 kmCanada

More tsunamis in United States

Source: NOAA National Centers for Environmental Information (NCEI), Global Historical Tsunami Database. Confirmed events only. Deaths and damage are database estimates; older records are incomplete. Water heights come from different types of observation.