Shallow M4.8 Earthquake struck on Friday Morning near Ponce in Puerto Rico.

Written by Earthquakelist.org on September 18th, 2026. Last updated September 19th, 2026.

In the morning of Friday September 18th, 2026, a shallow Magnitude 4.8 earthquake hit under land 35 kilometer from Ponce in Puerto Rico. Shaking may have been felt by a total of 2.4 million people. Other nearby countries are Dominican Republic, U.S. Virgin Islands and British Virgin Islands.

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Earthquake Summary

The earthquake struck on land in Puerto Rico, 35 kilometer (22 mi) west of Ponce. The center of this earthquake had a very shallow depth of 7 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Sep 18, 2026 09:19AM (Puerto Rico Time) - Sep 18, 2026 13:19 Universal Time.
Location:	35 km west of Ponce, Puerto Rico. Coordinates 17°56'21"N 66°56'44"W.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 4.8 Detected by 23 stations. Maximum Error Range ±0.079 .
Depth:	7 km (4 mi) A very shallow depth.
Max. Intensity:	V Moderate On the Modified Mercalli Scale.
Tsunami Risk:	Tsunami very unlikely While this was a shallow earthquake in a coastal area, it appears to have occurred under land (1 km from the sea) with a magnitude that is usually not strong enough to cause tsunami's. Always stay cautious - More info here.

Minimal impact predicted

Based on scientific estimates by the US Geographic Survey (USGS), the risk of high fatalities for this earthquake is classified at level GREEN (low). They expect an 90% likelyhood of between 0 and 1 fatalities.

The USGS classifies the economic impact of this earthquake at level GREEN (low). They expect an 90% likelyhood of between 0 and 1 million US Dollars in economic damage and impact.

Roughly 2.4 million people exposed to shaking

This earthquake may have been felt by around 2.4 million people. That is the expected population size of the area exposed to a level of shaking of II or higher on the Modified Mercalli scale according to the USGS.

Light shaking and likely no damage may have been experienced by an estimated 164,100 people. At IV, it is the highest MMI level this earthquake has caused. Intensity level II was experienced by the majority of people (around 1.2 million). In their region, very weak shaking and no damage can be expected.

People in 2 countries have been exposed to shaking. Roughly 2.4 million people were exposed to shaking in Puerto Rico , with level IV (light shaking, likely no damage) as the highest recorded.

Nearby towns and cities

This earthquake struck within proximity of multiple countries. Puerto Rico , Dominican Republic , U.S. Virgin Islands and British Virgin Islands are all within 300km distance of its epicenter.

Yauco in Yauco, Puerto Rico is the nearest significant place from the epicenter. The earthquake occurred 15 kilometer (9 mi) southwest of Yauco. The intensity of shaking and damage in Yauco is estimated to be around level IV on the Modified Mercalli Intensity scale (light shaking, likely no damage).

Major cities near this earthquake: Ponce is located 35 km to the east and experienced an intensity of III (weak shaking, probably no damage). San Juan is located 106 km to the north-east and experienced an intensity of II (very weak shaking, no damage). Bayamón is located 98 km to the north-east and experienced an intensity of III (weak shaking, probably no damage).

An overview of nearby towns and cities is available in the overview below. If places don't have intensity data available, it likely means the experienced impact in those places was fairly small.

Overview of nearby places

Earthquake Intensity Map

The maximum intensity (MMI Scale) caused by this earthquake is IV. The map below shows in which areas this earthquake was the most and least impactful. It is based on data from the US Geographic Survey.

I Not felt

II Weak

III Weak

IV Light

V Moderate

VI Strong

VII Very Strong

VIII Severe

IX Violent

X Extreme

19 Aftershocks detected

This main shock was followed by 19 smaller aftershocks. At a distance of 3 km (2.1 mi) northwest of this earthquake, an aftershock struck 4 hrs later. It measured a magnitude of 3.4

In the days before this main shock, 5 smaller foreshocks were detected. A 3.1 magnitude earthquake hit 1 day earlier nearby.

Overview of foreshocks and aftershocks

More earthquakes coming?

Aftershocks are usually at least 1 order of magnitude less strong than main shocks. The more time passes, the smaller the chance and likely strength of any potential aftershocks.

It's always adviced to be cautious of the risk of a larger shock following any significant earthquake, however this risk is fairly small. There is a roughly 94 percent change that no larger main shock will follow in the days following this earthquake.

Earthquakes like this happen often in the region

Earthquakes of this strength are very common in the region. This is the strongest earthquake to hit since July 24th, 2026, when a 4.8 magnitude earthquake hit 118 km (73 mi) further north. An even stronger magnitude 6.4 earthquake struck on January 7th, 2020.

In total, 57 earthquakes with a magnitude of 4.8 or higher have been registered within 300km (186 mi) of this epicenter in the past 10 years. This comes down to an average of once every 2 months.

Tsunami very unlikely

While MAG-6.5+ earthquakes may cause tsunami's, it appears that the epicenter of this earthquake hit under land. In addition, the reported depth is deeper than 100km, making the risk of a tsunami even less likely. However always stay cautious and monitor advice from local authorities.

Tsunami Risk Factors

Sources

Last updated 19/09/26 09:38 (). This article is automatically generated based on available data. We keep checking multiple sources for additional information. This article gets updated as new details on this earthquake become available.

1. US Geographic Society (USGS): Earthquake pr2026261000
2. European-Mediterranean Seismological Centre (EMSC): Earthquake 20260918_0000194
3. Geonames.org: World Cities Database
4. Google Maps: Static API
5. Earthquakelist.org: Historic Earthquakes Database

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