Earthquake · reviewed by a seismologist
M 1.5md
Earthquake near Los Altos Hills, CA
No earthquake was likely felt in Los Altos Hills in the 24 hours to 5:05 pm PST (01:05 UTC). The last one was M 2.0, 10 km (6 mi) SE, at 9:23 am PST on 10 November 2026, estimated intensity II (weak) in town; 4 felt reports to USGS. Every earthquake near Los Altos Hills
This page: a magnitude 1.5 earthquake was recorded in Los Altos Hills, CA, at 11:54 pm PDT on 27 July 2019 (06:54 UTC), 5.4 km deep. 1 person has reported feeling it to USGS.
USGS: 2km WSW of Los Altos Hills, CA
in Palo Alto, CA · 31 km (19 mi) WNW of San Jose, CA
- When
- 11:54 pm PDT on 27 July 2019 ()
- Where
- in Los Altos Hills, CA · earthquakes near Los Altos Hills
- Magnitude
- M 1.5 (md)
- Depth
- 5.4 km below the surface
- Felt
- 1 report · strongest reported intensity II
- Nearest
- San Mateo County, 20 km WNW
- Nearest mapped fault
- Monte Vista-Shannon fault, under 1 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 2659 days ago
Earthquake alerts for Los Altos Hills, CA
Get a notification in this browser when USGS records an earthquake near Los Altos Hills, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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. 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: Los Altos 4 km, intensity II · Mountain View 6 km, intensity II · Palo Alto 8 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 5.6 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.
- Mineral, Virginia 2011 M 5.8 2,700,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
- Around the size people start to feel M 3.0 170× the energy of this one
- This earthquake M 1.5 about 5.6 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 4.1 on 2017-10-10 — about 7,400 times the energy of this one.
Before 2016, the USGS record lists 16 earthquakes of M5 or more within 50 km; the five largest:
- 6.9 The 1989 Loma Prieta, California Earthquake · 45 km SSE of this epicentre
- 6.2 Near San Jose, California · 32 km ESE of this epicentre
- 6.2 The 1984 Morgan Hill, California Earthquake · 43 km E of this epicentre
- 6.1 Near San Jose, California · 37 km ESE of this epicentre
- 5.8 7 km NNW of Boulder Creek, California · 20 km S 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 37.3732, -122.1533. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| San Mateo County, CA | 20 km (12 mi) | WNW | earthquakes near San Mateo County |
| Alameda County, CA | 37 km (23 mi) | NE | earthquakes near Alameda County |
| Santa Cruz County, CA | 42 km (26 mi) | SSE | earthquakes near Santa Cruz County |
| Santa Clara County, CA | 44 km (28 mi) | ESE | earthquakes near Santa Clara County |
| Contra Costa County, CA | 63 km (39 mi) | NNE | earthquakes near Contra Costa County |
| San Francisco County, CA | 87 km (54 mi) | WNW | earthquakes near San Francisco County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
54 earthquakes have been recorded within 50 km since this one.
- 1.9 11km N of Morgan Hill, CA
- 3.3 8km ENE of Alum Rock, CA
- 2.0 9km ENE of Milpitas, CA
- 1.8 6km WSW of Colma, CA
- 1.9 6km WSW of Colma, CA
- 1.6 6km WSW of Colma, CA
- 3.5 5km WSW of Colma, CA
- 1.6 4km NNE of Dublin, CA
- 1.7 4km NNE of Dublin, CA
- 1.6 4km NNE of Dublin, CA
- 1.6 4km N of Dublin, CA
- 1.6 4km NNE of Dublin, CA
- 2.2 4km N of Dublin, CA
- 2.8 4km N of Dublin, CA
- 1.8 4km NNE of Dublin, CA
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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.