Every recorded earthquake within 30 km
Earthquakes near Diamond Bar, CA
No earthquake was likely felt in Diamond Bar in the 24 hours to 1:02 am PDT (08:02 UTC). The last one was M 3.6, 64 km (40 mi) WSW, at 8:40 am PDT on 27 September 2026, estimated intensity II (weak) in town; 1,735 felt reports to USGS.
M 3.2
Latest: 5:37 am PDT on 2 September 2026 · 20 km (13 mi) E of Diamond Bar, CA
The most recent earthquake of M2.5 or more near Diamond Bar was M 3.2, 20 km (13 mi) E of Diamond Bar, CA, at 5:37 am PDT on 2 September 2026, 6 km deep. 730 people reported feeling it to USGS. The estimated shaking in Diamond Bar was intensity II (weak), felt by some people at rest indoors. 7 smaller earthquakes have been recorded near Diamond Bar since; the newest is first in the list below.
No earthquake of M1.5 or more was recorded within 30 km (19 mi) of Diamond Bar in the last 24 hours.
- Last 24 hours
- 0
- Last 7 days
- 2
- Last 30 days
- 5 · an average 30 days here since 2016: 7.4
- Last 12 months
- 48 · largest M 3.2 on 2 September 2026
- Since 2016
- 970 earthquakes of M1.5 or more within 30 km
- Largest since 2016
- M 4.5 on 18 September 2020, 25 km (15 mi) W of Diamond Bar, CA
- Reported felt
- 468 of them have felt reports to USGS
- Nearest mapped fault
- Sierra Madre fault, 11 km from its surface trace
USGS · feed checked · newest earthquake in our database · this page · counts are earthquakes of M1.5 or more within 30 km (19 mi) of the town centre; shaking is estimated for the town centre with the intensity equation USGS Did You Feel It? uses
If you felt one
- Was that an earthquake? — checks what was recorded near you in the last hour
- Report what you felt to USGS — reports go to USGS, not to us, and they are what produces the intensity maps
- Expect aftershocks, and be ready to Drop, Cover, and Hold On if you feel one; if you are in a damaged building, go outside and move away from it (Ready.gov, FEMA; what to do during and after an earthquake)
- Near the coast, go inland or to higher ground as soon as strong shaking stops (Ready.gov); official warnings are on Tsunami.gov
- Earthquakes in California — with the state's activity score
QuakeIndex does not issue warnings or forecasts. For earthquake early warning see ShakeAlert and the MyShake app.
The last 30 days
The latest 50
- 1.7 21 km (13 mi) E of Diamond Bar, CA
- 1.5 19 km (12 mi) WNW of Diamond Bar, CA
- 1.9 21 km (13 mi) E of Diamond Bar, CA
- 1.7 21 km (13 mi) E of Diamond Bar, CA
- 1.6 15 km (10 mi) SW of Diamond Bar, CA
- 1.8 29 km (18 mi) SSE of Diamond Bar, CA
- 1.5 20 km (13 mi) E of Diamond Bar, CA
- 3.2 20 km (13 mi) E of Diamond Bar, CA · felt by 730
- 1.7 10 km (6 mi) NNE of Diamond Bar, CA
- 1.6 21 km (13 mi) E of Diamond Bar, CA
- 2.8 20 km (13 mi) E of Diamond Bar, CA · felt by 128
- 2.0 13 km (8 mi) SSW of Diamond Bar, CA · felt by 10
- 2.1 26 km (16 mi) SSE of Diamond Bar, CA · felt by 4
- 1.6 26 km (16 mi) SSE of Diamond Bar, CA
- 2.2 26 km (16 mi) SSE of Diamond Bar, CA · felt by 11
- 3.0 26 km (16 mi) SSE of Diamond Bar, CA · felt by 402
- 1.6 26 km (16 mi) SSE of Diamond Bar, CA
- 1.6 29 km (18 mi) WSW of Diamond Bar, CA
- 1.5 21 km (13 mi) E of Diamond Bar, CA
- 1.7 15 km (10 mi) SSW of Diamond Bar, CA
- 1.8 15 km (9 mi) WSW of Diamond Bar, CA
- 1.7 16 km (10 mi) SSW of Diamond Bar, CA
- 2.0 14 km (9 mi) N of Diamond Bar, CA
- 2.5 20 km (12 mi) E of Diamond Bar, CA · felt by 151
- 1.6 20 km (12 mi) SSE of Diamond Bar, CA
- 1.6 24 km (15 mi) E of Diamond Bar, CA
- 1.6 13 km (8 mi) SE of Diamond Bar, CA
- 2.0 18 km (11 mi) SSE of Diamond Bar, CA
- 1.6 17 km (11 mi) NNE of Diamond Bar, CA · felt by 1
- 1.5 10 km (6 mi) SSW of Diamond Bar, CA
- 1.8 14 km (9 mi) WNW of Diamond Bar, CA
- 1.7 4 km (3 mi) NE of Diamond Bar, CA
- 2.3 19 km (12 mi) E of Diamond Bar, CA · felt by 38
- 1.5 17 km (10 mi) SSE of Diamond Bar, CA
- 1.8 28 km (18 mi) E of Diamond Bar, CA · felt by 1
- 1.8 29 km (18 mi) E of Diamond Bar, CA · felt by 1
- 1.6 29 km (18 mi) NE of Diamond Bar, CA
- 1.8 17 km (10 mi) WNW of Diamond Bar, CA
- 1.9 28 km (17 mi) SSE of Diamond Bar, CA
- 1.5 26 km (16 mi) SE of Diamond Bar, CA
- 1.7 15 km (9 mi) N of Diamond Bar, CA
- 1.8 21 km (13 mi) NE of Diamond Bar, CA
- 1.6 21 km (13 mi) E of Diamond Bar, CA
- 1.6 30 km (19 mi) SSE of Diamond Bar, CA
- 1.9 9 km (5 mi) NNE of Diamond Bar, CA · felt by 1
- 1.8 15 km (9 mi) N of Diamond Bar, CA
- 1.5 18 km (11 mi) SSE of Diamond Bar, CA
- 1.5 20 km (12 mi) E of Diamond Bar, CA
- 2.3 16 km (10 mi) S of Diamond Bar, CA · felt by 1
- 1.5 29 km (18 mi) SSE of Diamond Bar, CA
From the QuakeIndex database, which reads the USGS feed every 30 seconds and holds the USGS catalogue for the US from 2016 (M1.5+). Times are Diamond Bar time. Distances are from the town centre. Quakes USGS named after Diamond Bar are listed even when they are further out.
Show these earthquakes on your own site: a free card with the latest quakes near Diamond Bar, for a local news site, school or neighborhood page.
On the map
The white circle is Diamond Bar; dots are the 50 most recent earthquakes within 30 km. Map © OpenStreetMap contributors.
Estimated shaking in Diamond Bar
The strongest shaking in Diamond Bar from a quake since 2016 is estimated at intensity IV (light), from the M 4.4 on 28 August 2018, 12 km away. Intensity II and III are felt by some people at rest indoors; IV by most people indoors; V and above wakes sleepers and moves objects.
| Magnitude | When | Distance | Shaking in Diamond Bar (est.) |
|---|---|---|---|
| M 4.4 | 12 km | IV · Light · felt by 6,155 | |
| M 4.5 | 25 km | III · Weak · felt by 21,402 | |
| M 4.0 | 20 km | III · Weak · felt by 6,217 | |
| M 4.0 | 20 km | III · Weak · felt by 2,758 | |
| M 4.1 | 29 km | III · Weak · felt by 8,407 |
An estimate for the town centre from magnitude, depth and distance, with the intensity equation USGS Did You Feel It? uses (Atkinson & Wald, 2007), on the Modified Mercalli scale. All 5 reach intensity II or more in town, where people at rest start to notice. Ground conditions change it street by street. It describes the past, not a hazard.
Before 2016
The USGS record since 1900 lists 14 earthquakes of M5 or more within 50 km of Diamond Bar; the five largest:
- 6.4 The 1933 Long Beach, California Earthquake · 48 km SSW of Diamond Bar
- 5.9 The 1987 Whittier Narrows, California Earthquake · 25 km W of Diamond Bar
- 5.8 The 1991 Sierra Madre, California Earthquake · 32 km NNW of Diamond Bar
- 5.5 The 1990 Upland, California Earthquake · 17 km NE of Diamond Bar
- 5.4 5km S of Chino Hills, CA · 10 km SSE of Diamond Bar
USGS ComCat, M5+ from 1900 to 2015. This is the record, not a forecast.
Nearest mapped faults
- Sierra Madre fault, 11 km from its surface trace
- Elsinore fault, 13 km from its surface trace
- Puente Hills blind thrust system, 15 km from its surface trace
USGS Quaternary Fault and Fold Database. Near is not the same as on.
Nearby towns
Walnut 5 km · Pomona 6 km · Chino Hills 6 km · San Dimas 9 km · South San Jose Hills 9 km · La Verne 9 km · Covina 10 km · Rowland Heights 11 km
Be ready
Earthquakes cannot be predicted, here or anywhere, so the useful step is the one taken beforehand. The advice below is from the agencies responsible for it.
- Ready.gov: earthquakes (FEMA) — what to do before, during and after, including Drop, Cover, and Hold On
- Build a kit (FEMA) — water, food and supplies for several days; our summary
- USGS: preparedness — the hazard behind the advice, from the agency that records every quake on this page
- The Great ShakeOut — the yearly earthquake drill, with material for homes, schools and workplaces
- ShakeAlert covers Diamond Bar, CA: alerts reach phones through Wireless Emergency Alerts and the MyShake app, seconds before shaking arrives
- Tsunami.gov (NOAA) — the official tsunami warnings for the coast; a quake page here never stands in for one
- California Earthquake Authority — retrofit grants and the state's not-for-profit earthquake insurance
QuakeIndex does not issue warnings or forecasts. For earthquake early warning see ShakeAlert and the MyShake app.