QuakeIndex

Earthquake · automatic estimate, may change

M 2.7md

Earthquake near Pacifica, CA

Yes. A magnitude 2.7 earthquake was recorded 2 km (1 mi) northeast of Pacifica, CA, at 5:17 pm PDT on 28 October 2026 (00:17 UTC), 6.5 km deep. 474 people have reported feeling it to USGS. The magnitude and location are an automatic first estimate and may change.

USGS: 2 km NE of Pacifica, CA

18 km (11 mi) SSW of San Francisco, CA · 8 km (5 mi) S of Daly City, CA

5:17 pm PDT, Oct 28, 2026 · · 6.5 km deep · released about 380 lb of TNT

10 km30 km60 km120 km N San Mateo County 25 kmAlameda County 49 kmSan Francisco County 51 kmMarin County 53 kmContra Costa County 56 kmSanta Cruz County 79 kmSanta Clara County 82 kmSolano County 85 kmNapa County 99 km
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
When
5:17 pm PDT on 28 October 2026 ()
Where
2 km (1 mi) northeast of Pacifica, CA · earthquakes near Pacifica
Magnitude
M 2.7 (md)
Depth
6.5 km below the surface
Felt
474 reports · strongest reported intensity IV
Nearest
San Mateo County, 25 km SSE
Nearest mapped fault
San Andreas fault, 1 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 2 hours 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 25 km (16 mi) from the epicentre. In Pacifica, 2 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: Pacifica 2 km, intensity III · San Bruno 5 km, intensity III · South San Francisco 6 km, intensity III · Millbrae 8 km, intensity III · Daly City 9 km, intensity III · Burlingame 10 km, intensity III · Bayview-Hunters Point 14 km, intensity II · San Mateo 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 380 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 40,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 29,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.5× the energy of this one
  4. This earthquake M 2.7 about 380 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 4.4 on 2018-01-04 — about 300 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 7.9 The 1906 San Francisco, California Earthquake · 16 km NNW of this epicentre
  2. 5.3 The 1957 San Francisco, California Earthquake · 5 km NNW 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 37.6258, -122.4685. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Mateo County, CA 25 km (16 mi) SSE earthquakes near San Mateo County
Alameda County, CA 49 km (30 mi) E earthquakes near Alameda County
San Francisco County, CA 51 km (32 mi) WNW earthquakes near San Francisco County
Marin County, CA 53 km (33 mi) NNW earthquakes near Marin County
Contra Costa County, CA 56 km (35 mi) NE earthquakes near Contra Costa County
Santa Cruz County, CA 79 km (49 mi) SSE earthquakes near Santa Cruz County

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

Aftershocks so far

No further earthquakes have been recorded within 50 km since this one.

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.

Revisions

USGS refines a solution as more stations report. Every change we have seen is listed here.

What changedFromToWhen
felt reports471474
felt reports469471
felt reports465469
felt reports460465
felt reports458460
felt reports457458
felt reports456457
felt reports453456
felt reports449453
felt reports445449
felt reports442445
felt reports435442

On USGS

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