QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6ml

Earthquake near Friday Harbor, WA

No earthquake was likely felt in Friday Harbor in the 24 hours to 9:39 am PST (17:39 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 2.6 earthquake was recorded 9 km (6 mi) northwest of Friday Harbor, WA, at 9:13 am PST on 31 December 2019 (17:13 UTC), 12 km deep. 24 people have reported feeling it to USGS.

USGS: 9 km NW of Friday Harbor, Washington

49 km (31 mi) WSW of Bellingham, WA · 122 km (76 mi) NNW of Seattle, WA

9:13 am PST, Dec 31, 2019 · · 12 km deep · released about 240 lb of TNT

10 km30 km60 km120 km N San Juan County 10 kmIsland County 58 kmClallam County 79 kmJefferson County 93 kmSkagit County 95 kmWhatcom County 97 kmKitsap County 111 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
9:13 am PST on 31 December 2019 ()
Where
9 km (6 mi) northwest of Friday Harbor, WA · earthquakes near Friday Harbor
Magnitude
M 2.6 (ml)
Depth
12 km below the surface
Felt
24 reports · strongest reported intensity III
Nearest
San Juan County, 10 km S
Nearest mapped fault
Utsalady Point fault, 24 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2373 days 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 21 km (13 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 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 · 25 km ENE of this epicentre
  2. 5.5 21 km SSE of Point Roberts, Washington · 24 km NNE of this epicentre
  3. 5.1 10 km ESE of Salt Spring Island, Canada · 30 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 48.5950, -123.0990. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan County, WA 10 km (6 mi) S earthquakes near San Juan County
Island County, WA 58 km (36 mi) SSE earthquakes near Island County
Clallam County, WA 79 km (49 mi) SW earthquakes near Clallam County
Jefferson County, WA 93 km (58 mi) SSW earthquakes near Jefferson County
Skagit County, WA 95 km (59 mi) E earthquakes near Skagit County
Whatcom County, WA 97 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

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

  1. 2.0 7 km NNE of Jamestown, Washington
  2. 2.3 1 km W of Oak Harbor, Washington
  3. 2.2 16 km NNW of Jamestown, Washington
  4. 1.7 12 km ESE of Salt Spring Island, Canada
  5. 2.5 6 km ESE of Oak Bay, Canada
  6. 1.6 9 km E of North Saanich, Canada
  7. 2.8 6 km E of North Saanich, Canada
  8. 1.7 15 km NW of Orcas, Washington
  9. 1.6 7 km NNW of Ganges, Canada
  10. 1.9 3 km N of Langford, Canada
  11. 2.2 5 km NE of Oak Harbor, Washington
  12. 1.8 6 km WNW of Coupeville, Washington
  13. 1.7 8 km NNW of Friday Harbor, Washington
  14. 1.7 5 km NNE of Anacortes, Washington
  15. 2.3 5 km N of Anacortes, 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.