M3.3 earthquake on San Jacinto fault near Redlands draws 455 felt reports

An M3.3 earthquake struck 6 km south-southwest of Redlands, California on April 27, 2026 at 7:47 AM PDT (14:47:13 UTC). USGS placed the epicenter in Riverside County at a depth of 3.3 kilometers, about 0.1 km from the mapped trace of the San Jacinto fault (San Bernardino Valley section).

The event drew 455 "Did You Feel It?" reports submitted to USGS, with a community-reported intensity (CDI) of 3.4. ShakeMap modeled a maximum instrumental intensity (MMI) of 3.6. Both values are consistent with weak-to-light shaking felt indoors across the surrounding area.

At a depth of 3.3 km, the event is very shallow — earthquakes at this depth typically produce stronger surface shaking than deeper events of the same magnitude. USGS assigned a significance score of 319 on its internal 0–1000 scale.

Riverside County has a population of approximately 2,280,000. USGS PAGER did not produce a population-exposure estimate for this event.

USGS catalog data shows 13 other M3.3+ earthquakes within 20 km of this epicenter in the past 10 years, suggesting events of this size occur about once every 0.8 years at this location.

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Event data

• Magnitude: M3.3 (Ml)
• Depth: 3.29 km
• Time: 2026-04-27 07:47 AM PDT (14:47:13 UTC)
• Coordinates: 34.0027°N, -117.2105°W
• County: Riverside
• Nearest mapped fault: San Jacinto fault (San Bernardino Valley section), 0.1 km
• USGS event page: https://earthquake.usgs.gov/earthquakes/eventpage/ci41235031