QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near McCall, ID

No earthquake was likely felt in McCall in the 24 hours to 9:33 am MST (16:33 UTC). The last one was M 4.3, 83 km (52 mi) WNW, at 12:42 am MST on 10 November 2026, estimated intensity II (weak) in town; 134 felt reports to USGS. Every earthquake near McCall

This page: a magnitude 1.8 earthquake was recorded 47 km (29 mi) southeast of McCall, ID, at 4:21 am MDT on 18 August 2020 (10:21 UTC), 9.6 km deep.

USGS: 33 km ENE of Cascade, Idaho

4:21 am MDT, Aug 18, 2020 · · 9.6 km deep · released about 17 lb of TNT

10 km30 km60 km120 km N Valley County 25 kmAdams County 70 kmBoise County 72 kmGem County 87 kmWashington County 93 kmPayette County 112 kmCuster County 118 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
4:21 am MDT on 18 August 2020 ()
Where
47 km (29 mi) southeast of McCall, ID · earthquakes near McCall
Idaho today
every earthquake in Idaho in the last 24 hours
Magnitude
M 1.8 (ml)
Depth
9.6 km below the surface
Felt
no reports yet
Nearest
Valley County, 25 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2277 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 10 km (6 mi) from the epicentre. In McCall, 47 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 17 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 870,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 620,000× the energy of this one
  3. Around the size people start to feel M 3.0 55× the energy of this one
  4. This earthquake M 1.8 about 17 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 6.5 on 2020-03-31 — about 9,800,000 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 6.0 44 km NNW of Stanley, Idaho · 45 km E 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 44.6355, -115.6480. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Valley County, ID 25 km (15 mi) N earthquakes near Valley County
Adams County, ID 70 km (43 mi) WNW earthquakes near Adams County
Boise County, ID 72 km (45 mi) S earthquakes near Boise County
Gem County, ID 87 km (54 mi) SW earthquakes near Gem County
Washington County, ID 93 km (58 mi) WSW earthquakes near Washington County
Payette County, ID 112 km (70 mi) SW earthquakes near Payette County

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

Aftershocks so far

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

  1. 2.1 35 km NW of Stanley, Idaho
  2. 2.3 34 km NW of Stanley, Idaho
  3. 2.5 41 km NW of Stanley, Idaho
  4. 2.3 44 km NNW of Stanley, Idaho
  5. 2.5 43 km NNW of Stanley, Idaho
  6. 2.4 26 km NW of Stanley, Idaho
  7. 1.6 26 km NW of Stanley, Idaho
  8. 2.3 43 km NNW of Stanley, Idaho
  9. 2.5 45 km NW of Stanley, Idaho
  10. 1.9 39 km NW of Stanley, Idaho
  11. 2.4 24 km WNW of Stanley, Idaho
  12. 2.9 43 km NW of Stanley, Idaho
  13. 1.6 southern Idaho
  14. 3.3 37 km NW of Stanley, Idaho
  15. 2.3 25 km NW of Stanley, Idaho

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.