QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

Earthquake near Friday Harbor, WA

No earthquake was likely felt in Friday Harbor in the 24 hours to 10:23 pm PST (06:23 UTC). The last one was M 3.8, 41 km (25 mi) SE, at 11:35 pm PDT on 1 July 2026, estimated intensity II (weak) in town; 2,030 felt reports to USGS. Every earthquake near Friday Harbor

This page: a magnitude 2.5 earthquake was recorded 9 km (6 mi) northwest of Friday Harbor, WA, at 9:03 pm PDT on 30 October 2020 (04:03 UTC), 12 km deep. 26 people have reported feeling it to USGS.

USGS: 9 km NW of Friday Harbor, Washington

49 km (30 mi) WSW of Bellingham, WA · 122 km (76 mi) NNW of Seattle, WA

9:03 pm PDT, Oct 30, 2020 · · 12 km deep · released about 150 lb of TNT

Every earthquake near Friday Harbor Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Juan County 11 kmIsland County 58 kmClallam County 80 kmJefferson County 94 kmSkagit County 95 kmWhatcom County 96 kmKitsap County 112 kmSnohomish County 115 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
9:03 pm PDT on 30 October 2020 ()
Where
9 km (6 mi) northwest of Friday Harbor, WA · earthquakes near Friday Harbor
Magnitude
M 2.5 (ml)
Depth
12 km below the surface
Felt
26 reports · strongest reported intensity III
Nearest
San Juan County, 11 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2124 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 18 km (11 mi) from the epicentre. In Friday Harbor, 9 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: Friday Harbor 9 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 150 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 72,000× the energy of this one
  3. Around the size people start to feel M 3.0 6.5× the energy of this one
  4. This earthquake M 2.5 about 150 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 3 earthquakes of M5 or more within 50 km:

  1. 6.0 San Juan Islands, Washington · 24 km ENE of this epicentre
  2. 5.5 21 km SSE of Point Roberts, Washington · 23 km NNE of this epicentre
  3. 5.1 10 km ESE of Salt Spring Island, Canada · 29 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 48.6027, -123.0918. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan County, WA 11 km (7 mi) S earthquakes near San Juan County
Island County, WA 58 km (36 mi) SSE earthquakes near Island County
Clallam County, WA 80 km (50 mi) SW earthquakes near Clallam County
Jefferson County, WA 94 km (59 mi) SSW earthquakes near Jefferson County
Skagit County, WA 95 km (59 mi) E earthquakes near Skagit County
Whatcom County, WA 96 km (60 mi) ENE earthquakes near Whatcom County

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

Aftershocks so far

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

  1. 1.6 5 km N of Oak Bay, Canada
  2. 2.3 5 km NNE of Oak Bay, Canada
  3. 1.6 8 km NE of Oak Bay, Canada
  4. 1.6 11 km E of North Saanich, Canada
  5. 1.7 9 km NW of Langford, Canada
  6. 1.6 9 km NW of Orcas, Washington
  7. 1.6 8 km NNW of Jamestown, Washington
  8. 1.5 16 km NE of Jamestown, Washington
  9. 1.7 2 km N of Metchosin, Canada
  10. 2.3 Washington-British Columbia border region
  11. 1.5 2 km NW of Orcas, Washington
  12. 2.0 6 km W of Orcas, Washington
  13. 1.6 5 km NNW of Victoria, Canada
  14. 1.5 10 km NNW of Anacortes, Washington
  15. 1.8 9 km WSW of Friday Harbor, 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.