M 5.8 in Tonga on 21 May 2023 05:23 UTC

Hazard models

Rapid Impact
Shakemap
Tsunami

Event summary

This earthquake is expected to have a low humanitarian impact based on the magnitude and the affected population and their vulnerability.

Earthquake Magnitude: 5.8M
Depth: 10 Km
Lat/Lon: -19.4133 , -173.3266
Event Date: 21 May 2023 05:23 UTC
20 May 2023 17:23 Local
Exposed Population: 4 thousand in MMI IV
Source: NEIC us6000kdk8
Inserted at: 21 May 2023 05:41 UTC
INFORM Coping capacity of the alert score: 1.1 (Tonga)

GDACS Score

For more info on GDACS alert score click here.
  Earthquake
(Shakemap)		 GDACS score
NEIC 0 0
us6000kdk8 Scaled population (raster) 0  
  C1 shakemap 0  
  C2 shakemap 0  
  Country Vulnerability 0  
  INFORM_normalised 0  
Maximum expected impact using different data sources.

ShakeMap is a product of the USGS Earthquake Hazards Program in conjunction with the regional seismic networks. ShakeMaps provide near-real-time maps of ground motion and shaking intensity following significant earthquakes.


Episode Timeline

IDAlertScoreDateMag, DepthMMI*Population**Tsunami risk***Delay (hh:mm)Source
1506791 0 21 May 2023 05:23 5.8M, 10km 3.54 N/A (in MMI>=VII) 00:18 NEIC
The episode that generated the alert; the next major evaluations beyond 12 hours will not trigger additional alerts.
The episode that has the last updated information.
* The max MMI detected for sources having shakemaps;
** The population detected in MMI>=7 for episode with shakemap or in a 100km radius;
*** The tsunami max height.

Exposed population

The earthquake happened in Tonga ,of Tonga (population 12,748) . The alertlevel for this event is GREEN

Intensity Population
no people


Shakemaps Timeline

AlertShake id #ScoreepisodeidLat/LonMagnitudeDepthMax MMIDate shake (UTC)Delay (hh:mm) 
1 0 1506791 -173.327/-19.413 5.8 10 3.532 21 May 2023 05:46 00:23 (new episode)
2 0 1506791 -173.327/-19.413 5.8 10 3.491 21 May 2023 05:55 00:32 (upd of #1)
3 0 1506791 -173.327/-19.413 5.8 10 3.536 21 May 2023 07:27 02:04 (upd of #2)
4 0 1506791 -173.327/-19.413 5.8 10 3.536 22 May 2023 05:41 1d 00:17 (upd of #3)

Affected Provinces

Intensity Region Province Country Population
Tonga Tonga 13000 people

Affected populated places. Areas of interest

Intensity Name Region Province Country City class Population Distance
Neiafu Tonga Village 4300 people 109 km
Pangai Tonga Village 1700 people 117 km
Kolonga Tonga Village - 265 km

see full list


Critical infrastructure

Airports, ports, nuclear plants and hydrodams at risk, if affected, are listed below.

Airports

Intensity Name IATA Code Elevation (m) Usage Runway type IFR Runway Length (ft) Distance
Vavau International VAV 72 Civ. Unpaved Yes 5500 113 km
Haapai HPA 12 Civ. Unpaved Yes 3900 114 km

Ports

Intensity Name LOCODE Country Distance
Neiafu TONEI Tonga 109 km
Pangai TOPAN Tonga 116 km

More information

For a full list of available products related to this event, please refer to the GDACS Resources page.