QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

Earthquake near Redlands, CA

No earthquake was likely felt in Redlands in the 24 hours to 6:07 am PST (14:07 UTC). The last one was M 2.0, 9 km (5 mi) SSE, at 10:33 pm PST on 2 November 2026, estimated intensity II (weak) in town. Every earthquake near Redlands

This page: a magnitude 2.7 earthquake was recorded 4 km (3 mi) south-southeast of Redlands, CA, at 2:07 am PDT on 4 April 2026 (09:07 UTC), 9.3 km deep. 28 people have reported feeling it to USGS.

USGS: 4 km SSE of Redlands, CA

in Redlands, CA · 114 km (71 mi) E of Los Angeles, CA

2:07 am PDT, Apr 4, 2026 · · 9.3 km deep · released about 320 lb of TNT

10 km30 km60 km120 km N Orange County 68 kmLos Angeles County 102 kmRiverside County 113 kmSan Diego County 117 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
2:07 am PDT on 4 April 2026 ()
Where
4 km (3 mi) south-southeast of Redlands, CA · earthquakes near Redlands
Magnitude
M 2.7 (ml)
Depth
9.3 km below the surface
Felt
28 reports · strongest reported intensity III
Nearest
Orange County, 68 km SW
Nearest mapped fault
Crafton Hills fault, under 1 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 145 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 23 km (14 mi) from the epicentre. In Redlands, 4 km away, the estimate is intensity III (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Redlands 4 km, intensity III · Mentone 7 km, intensity III · Loma Linda 9 km, intensity III · Moreno Valley 11 km, intensity II · Yucaipa 12 km, intensity II · Highland 13 km, intensity II · Colton 14 km, intensity II · San Bernardino 15 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 320 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 48,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 34,000× the energy of this one
  3. Around the size people start to feel M 3.0 3× the energy of this one
  4. This earthquake M 2.7 about 320 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

The largest earthquake within 50 km since 2016 was M 4.5 on 2018-05-08 — about 520 times the energy of this one.

Before 2016, the USGS record lists 23 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1918 San Jacinto, California Earthquake · 34 km SSE of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 38 km ENE of this epicentre
  3. 6.2 3 km SE of San Bernardino, California · 11 km NW of this epicentre
  4. 6.0 The 1910 Lake Elsinore, California Earthquake · 41 km SSW of this epicentre
  5. 5.6 7km ENE of Running Springs, CA · 27 km NNE of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 34.0193, -117.1732. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 68 km (42 mi) SW earthquakes near Orange County
Los Angeles County, CA 102 km (63 mi) WNW earthquakes near Los Angeles County
Riverside County, CA 113 km (70 mi) ESE earthquakes near Riverside County
San Diego County, CA 117 km (73 mi) SSE earthquakes near San Diego County
San Bernardino County, CA 130 km (81 mi) NE earthquakes near San Bernardino County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

57 earthquakes have been recorded within 50 km since this one.

  1. 2.0 6 km NE of Cabazon, CA
  2. 2.3 8 km SE of Winchester, CA
  3. 1.8 6 km SSW of Redlands, CA
  4. 2.2 3 km ESE of Loma Linda, CA
  5. 3.3 1 km SE of Muscoy, CA
  6. 3.2 7 km SE of Loma Linda, CA
  7. 1.6 7 km SE of Loma Linda, CA
  8. 3.1 7 km SE of Loma Linda, CA
  9. 1.5 6 km SSE of Home Gardens, CA
  10. 1.5 7 km SE of Loma Linda, CA
  11. 1.8 5 km SE of Loma Linda, CA
  12. 1.7 7 km SE of Loma Linda, CA
  13. 2.0 6 km SSW of Redlands, CA
  14. 1.7 6 km SSW of Redlands, CA
  15. 1.9 6 km SSW of Redlands, CA

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.