3.3

M3.3 Earthquake 6 km SSW of Redlands, CAApril 27, 2026

2026-04-27 14:47:13 UTC (2 hours ago) · approx. 6:47 AM UTC-8 local

Felt by 431 people across surrounding communities.

MagnitudeM3.3(ml)
Time14:47 UTC6:47 AM UTC-8
Depth3.3 kmshallow crustal
Coordinates34.003°, -117.210°
Felt by431DYFI responses· max MMI 3.6
Status✓ Reviewed by USGS

On April 27, 2026 at 14:47 UTC, a magnitude 3.3 shallow crustal earthquake struck 6 km SSW of Redlands, CA, at a depth of 3.3 km and coordinates 34.0027°, -117.2105°. The earthquake was reported felt by 431 peopleacross surrounding communities, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.6 (light). This earthquake was detected by 129 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 311, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 3.3 releases seismic energy equivalent to roughly 1.2 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 109 m — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in California, a region characterized by the San Andreas transform fault system, where the Pacific and North American plates slide past each other at roughly 46 mm per year. The nearest mapped fault system is the San Andreas Fault. View all earthquakes in California.

Learn more: San Andreas Fault · Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at 34.00°, -117.21°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M3.3 earthquake near 6 km SSW of Redlands, CA

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 431 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M3.3 earthquake near 6 km SSW of Redlands, CA

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
3.3 ml
Depth
3.3 km
shallow crustal
Location
34.0027°N
-117.2105°E
Felt Reports
431
DYFI responses
Intensity (MMI)
3.6
light
Community Intensity
3.4
CDI from reports

Technical Information

Event ID
ci41235031
Event Type
earthquake
Status
✓ Reviewed
Significance
311
Stations Used
129
Azimuthal Gap
25.0°
Min Station Distance
0.063°
RMS Residual
0.21 sec
Last Updated
2026-04-27 16:38:19 UTC

Common Questions

How strong was the magnitude 3.3 earthquake near Redlands, CA?

The magnitude 3.3 earthquake that struck 6 km SSW of Redlands, CA on April 27, 2026 at 14:47 UTC had a depth of 3.3 km. It was felt by 431 people with maximum shaking intensity of MMI 3.6 (light). For context, this was a minor earthquake typically detected only by instruments.

Where did the earthquake occur?

The earthquake epicenter was located at 34.0027°, -117.2105°, which is 6 km SSW of Redlands, CA. View all earthquakes in California.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.3 earthquakes can continue for several days and gradually diminish over time.

Has California had earthquakes this big before?

The largest recorded earthquake in California was the M7.9 Fort Tejon earthquake of January 9, 1857. Today's magnitude 3.3 event is significantly smaller than that historical record.

What should I do after an earthquake?

If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.

Authoritative source: USGS event page (event ID: ci41235031). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, April 27, 2026). M3.3 Earthquake 6 km SSW of Redlands, CAApril 27, 2026. Retrieved April 27, 2026 from https://www.earthquaketracker.org/earthquakes/event/ci41235031/