QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Mount Vernon, WA

No earthquake was likely felt in Mount Vernon in the 24 hours to 6:45 am PST (14:45 UTC). The last one was M 2.6, 2 km (1 mi) ENE, at 9:17 pm PDT on 11 September 2026, estimated intensity II (weak) in town; 10 felt reports to USGS. Every earthquake near Mount Vernon

This page: a magnitude 1.5 earthquake was recorded 41 km (25 mi) east-northeast of Mount Vernon, WA, at 2:31 pm PST on 4 November 2025 (22:31 UTC), 5.0 km deep.

USGS: 4 km WSW of Concrete, Washington

55 km (34 mi) ESE of Bellingham, WA · 109 km (68 mi) NNE of Seattle, WA

2:31 pm PST, Nov 4, 2025 · · 5.0 km deep · released about 5.7 lb of TNT

10 km30 km60 km120 km N Skagit County 4 kmWhatcom County 35 kmSnohomish County 53 kmIsland County 76 kmSan Juan County 95 kmChelan County 115 kmKing County 115 kmKitsap 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
2:31 pm PST on 4 November 2025 ()
Where
41 km (25 mi) east-northeast of Mount Vernon, WA · earthquakes near Mount Vernon
Magnitude
M 1.5 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Skagit County, 4 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 374 days ago

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 9 km (6 mi) from the epicentre. In Mount Vernon, 41 km away, the estimate is intensity I (not felt). 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.

How big was it?

This earthquake released about 5.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

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

  1. 5.6 Near Marblemount, Washington · 30 km E of this epicentre
  2. 5.0 4 km ENE of Deming, Washington · 44 km NW 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 48.5275, -121.8080. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Skagit County, WA 4 km (2 mi) S earthquakes near Skagit County
Whatcom County, WA 35 km (22 mi) N earthquakes near Whatcom County
Snohomish County, WA 53 km (33 mi) S earthquakes near Snohomish County
Island County, WA 76 km (47 mi) WSW earthquakes near Island County
San Juan County, WA 95 km (59 mi) W earthquakes near San Juan County
Chelan County, WA 115 km (72 mi) SE earthquakes near Chelan County

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

Aftershocks so far

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

  1. 1.0 8 km NW of Swede Heaven, Washington
  2. 0.7 10 km S of Acme, Washington
  3. 2.6 2 km ENE of Granite Falls, Washington
  4. 1.0 5 km SW of Darrington, Washington
  5. 1.2 1 km WNW of Acme, Washington
  6. 1.5 4 km ENE of Granite Falls, Washington
  7. 0.9 3 km ENE of Swede Heaven, Washington
  8. 1.3 2 km ENE of Granite Falls, Washington
  9. 0.4 7 km NE of Sedro-Woolley, Washington
  10. 1.1 11 km N of Concrete, Washington
  11. 0.9 2 km WNW of Lyman, Washington
  12. 1.0 2 km ENE of Granite Falls, Washington
  13. 1.1 3 km NNE of Lyman, Washington
  14. 1.4 5 km ENE of Sudden Valley, Washington
  15. 1.1 6 km NE of Oso, Washington

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.