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Light mag. 4.4 earthquake - 3km NE of Westmorland, CA, USA on Wednesday, 30 September 2020

This quake was likely a foreshock of the 4.9 quake 4km NE of Westmorland, CA, USA, 1 Oct 2020 00:31 UTC, which followed after 60 minutes.
Light mag. 4.4 earthquake  - 3km NE of Westmorland, CA, USA on Wednesday, 30 September 2020
30 Sep 23:33 UTC: First to report: USGS after 2 minutes.
30 Sep 23:35: Magnitude recalculated from 4.3 to 3.9. Hypocenter depth recalculated from 9.0 to 7.5 km (from 5.6 to 4.7 mi). Epicenter location corrected by 1.8 km (1.1 mi) towards WNW.
30 Sep 23:38: Magnitude recalculated from 3.9 to 4.4.
1 Oct 00:14: Hypocenter depth recalculated from 7.5 to 4.8 km (from 4.7 to 3 mi).
Date & time: Wednesday, 30 September 2020 23:31 UTC
Local time at epicenter: 30 Sep 4:31 pm (GMT -7)
Magnitude: 4.4
Depth: 4.8 km
Epicenter latitude / longitude: 33.053°N / 115.5955°W (United States)
Nearest volcano: Salton Buttes (17 km / 11 mi)
Nearby towns and cities:
3 km (2 mi) NE of Westmorland (pop: 2,300)
10 km (6 mi) NW of Brawley (pop: 25,900)
11 km (7 mi) SW of Calipatria (pop: 7,400)
49 km (31 mi) NW of Mexicali (pop: 597,100)
145 km (90 mi) NE of Tijuana (pop: 1,376,500)
151 km (94 mi) NE of San Diego (pop: 1,394,900)
Weather at epicenter at time of quake:
Clear Sky 42°C (108 F), humidity: 6%, wind: 2 m/s (4 kts) from NNW
Primary data source: USGS
Estimated released energy: 2.5 x 1011 joules (69.8 megawatt hours, equivalent to 60 tons of TNT) [learn more]
If you felt this quake (or if you were near the epicenter), please share your experience and submit a short "I felt it" report! Other users would love to hear about it!
Also if you did NOT feel the quake although you were in the area, please report it! Your contribution is valuable also to earthquake science and earthquake hazard analysis and mitigation efforts. You can use your device location or the map to indicate where you were during the earthquake. Thank you!

Data for the same earthquake reported by different agencies

Info: The more agencies report about the same quake and post similar data, the more confidence you can have in the data. It takes normally up to a few hours until earthquake parameters are calculated with near-optimum precision.
TimeMag. / DepthLocationSource
30 Sep 4:31 pm (GMT -7) (30 Sep 23:31:51 UTC)M 4.4 / 4.8 km3km NE of Westmorland, CA, USAUSGS

User reports for this quake (6)

User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
5.6 km E of epicenter [Map] / Moderate shaking (MMI V) / single lateral shake
Coachella, CA (86.4 km NW of epicenter) [Map] / Very weak shaking (MMI II) / horizontal (sideways) swinging / 15-20 s
10.2 km SE of epicenter [Map] / Moderate shaking (MMI V) / horizontal (sideways) swinging / 2-5 s (reported through our app)
306.5 km WNW of epicenter [Map] / Moderate shaking (MMI V) (reported through our app)
10.2 km SE of epicenter [Map] / Moderate shaking (MMI V) (reported through our app)
4th Ave, El Centro / Moderate shaking (MMI V) / horizontal (sideways) swinging / 20-30 s

Earlier earthquakes in the same area since 1900

Light mag. 4.4 earthquake - 3km NE of Westmorland, CA, USA on Wednesday, 30 September 2020

Map of earlier quakes


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