Earthquake · reviewed by a seismologist
M 1.8ml
Earthquake near Big Bear Lake, CA
No earthquake was likely felt in Big Bear Lake in the 24 hours to 4:19 am PST (12:19 UTC). The last one was M 2.6, 7 km (4 mi) NE, at 1:40 am PDT on 6 October 2026, estimated intensity III (weak) in town; 18 felt reports to USGS. Every earthquake near Big Bear Lake
This page: a magnitude 1.8 earthquake was recorded 6 km (4 mi) southeast of Big Bear Lake, CA, at 3:39 pm PST on 27 February 2020 (23:39 UTC), 2.6 km deep.
USGS: 6 km SE of Big Bear Lake, CA
24 km (15 mi) NE of Yucaipa, CA · 143 km (89 mi) E of Los Angeles, CA
- When
- 3:39 pm PST on 27 February 2020 ()
- Where
- 6 km (4 mi) southeast of Big Bear Lake, CA · earthquakes near Big Bear Lake
- Magnitude
- M 1.8 (ml)
- Depth
- 2.6 km below the surface
- Felt
- no reports yet
- Nearest
- Riverside County, 96 km ESE
- Nearest mapped fault
- Helendale-South Lockhart fault, 13 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 960 days ago
Earthquake alerts for Big Bear Lake, CA
Get a notification in this browser when USGS records an earthquake near Big Bear Lake, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth, people at rest would likely notice it out to about 14 km (9 mi) from the epicentre. In Big Bear Lake, 6 km away, the estimate is intensity II (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: Big Bear Lake 6 km, intensity II · Big Bear City 7 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 17 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 870,000× the energy of this one
- Magna, Utah 2020 M 5.7 620,000× the energy of this one
- Around the size people start to feel M 3.0 55× the energy of this one
- This earthquake M 1.8 about 17 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 9,400 times the energy of this one.
Before 2016, the USGS record lists 32 earthquakes of M5 or more within 50 km; the five largest:
- 7.3 The 1992 Landers, California Earthquake · 40 km E of this epicentre
- 6.7 The 1918 San Jacinto, California Earthquake · 50 km S of this epicentre
- 6.3 The 1992 Big Bear, California Earthquake · 4 km E of this epicentre
- 6.2 3 km SE of San Bernardino, California · 38 km WSW of this epicentre
- 6.0 The 1986 North Palm Springs, California Earthquake · 33 km SE 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 34.2027, -116.8750. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Riverside County, CA | 96 km (60 mi) | ESE | earthquakes near Riverside County |
| San Bernardino County, CA | 97 km (60 mi) | NE | earthquakes near San Bernardino County |
| Orange County, CA | 102 km (63 mi) | SW | earthquakes near Orange County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
55 earthquakes have been recorded within 50 km since this one.
- 1.7 10km SSE of Lucerne Valley, CA
- 2.0 10km SSE of Lucerne Valley, CA
- 1.7 1km ESE of Redlands, CA
- 1.8 1km SE of Redlands, CA
- 1.6 1km ESE of Redlands, CA
- 1.6 6km S of Redlands, CA
- 1.8 6km E of Calimesa, CA
- 1.6 4km SE of Loma Linda, CA
- 1.9 11km WSW of Garnet, CA
- 2.5 2km NNE of Lake Arrowhead, CA
- 1.8 29km N of Yucca Valley, CA
- 1.6 26km N of Yucca Valley, CA
- 2.5 8km SW of Calimesa, CA
- 1.5 6km NW of Calimesa, CA
- 1.5 22km N of Yucca Valley, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.