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Post ShakeAlert Message Summaries


Post ShakeAlert Message Summaries provide information about earthquakes detected by the ShakeAlert Earthquake Early Warning System and ShakeAlert’s performance during these events. They summarize how accurately the ShakeAlert System estimated the earthquake’s location and magnitude, how many seismic stations contributed data to these estimates, and how much warning time nearby cities may have received. These summaries are automatically generated for all USGS-issued ShakeAlert Messages with an estimated peak magnitude (M) of 3.5 or larger. Only at M 4.0 or larger are ShakeAlert Messages human-reviewed and forwarded to the National Earthquake Information Center to be posted at www.earthquake.usgs.gov. Summaries for earthquakes less than M 4.0 provide our scientists with more frequent tests of software readiness, but their results are generally not reviewed for quality or accuracy.

Please Note: USGS does not warrant that this information resource will be available without interruption, be error-free, or that any errors must be corrected. Post ShakeAlert Message Summaries are provided “AS IS” and without any warranty, express, implied, or otherwise, regarding its accuracy or performance. Any reliance upon this resource is at the express and sole risk of the user, including its employees, assigns, and insurers.

FileDate PostedSize
1662_2020-08-19_014342_6_6_mi_SE_of_Willits_3_5.pdf
August 19, 2020 310.86 KB
1661_2020-08-19_005523_6_8_mi_SE_of_Willits_4_0.pdf
August 19, 2020 313.16 KB
1660_2020-08-19_004616_6_5_mi_SE_of_Willits_3_1.pdf
August 19, 2020 311.38 KB
1658_2020-08-17_150906_80_8_mi_S_of_Mexicali_B_C__4_4.pdf
August 17, 2020 247.67 KB
1657_2020-08-12_114543_13_6_mi_NE_of_Healdsburg_4_0.pdf
August 12, 2020 325.08 KB
1656_2020-08-11_111958_12_9_mi_NW_of_Calipatria_3_2.pdf
August 11, 2020 310.87 KB
1655_2020-08-10_192929_13_7_mi_NW_of_Calipatria_3_6.pdf
August 10, 2020 308.29 KB
1654_2020-08-10_185321_14_2_mi_NW_of_Calipatria_3_2.pdf
August 10, 2020 307.39 KB
1653_2020-08-10_161354_18_1_mi_NW_of_Calipatria_2_4.pdf
August 10, 2020 305.60 KB
1652_2020-08-10_160339_13_0_mi_NW_of_Calipatria_3_5.pdf
August 10, 2020 307.33 KB
1651_2020-08-10_155615_12_8_mi_NW_of_Calipatria_4_0.pdf
August 10, 2020 323.06 KB
1650_2020-08-10_155548_13_5_mi_NW_of_Calipatria_3_5.pdf
August 10, 2020 312.29 KB
1649_2020-08-09_032355_30_6_mi_SW_of_Rio_Dell_3_7.pdf
August 09, 2020 198.63 KB
1648_2020-08-09_000035_32_2_mi_SW_of_Rio_Dell_3_7.pdf
August 09, 2020 194.25 KB
1647_2020-07-30_134819_0_8_mi_N_of_San_Fernando_3_9.pdf
July 30, 2020 345.26 KB
1646_2020-07-30_112929_1_4_mi_N_of_San_Fernando_4_2.pdf
July 30, 2020 348.61 KB
1645_2020-07-30_032301_20_3_mi_E_of_King_City_4_1.pdf
July 30, 2020 312.16 KB
1644_2020-07-24_070513_59_1_mi_N_of_Ridgecrest_3_6.pdf
July 24, 2020 293.13 KB
1643_2020-07-23_002926_59_5_mi_N_of_Ridgecrest_3_6.pdf
July 23, 2020 293.89 KB
1642_2020-07-22_045709_12_9_mi_SE_of_Hollister_3_5.pdf
July 22, 2020 337.18 KB
1641_2020-07-20_220153_21_4_mi_SW_of_Arvin_3_5.pdf
July 20, 2020 335.51 KB
1640_2020-07-05_161407_13_5_mi_NE_of_Healdsburg_3_9.pdf
July 05, 2020 321.87 KB
1639_2020-07-05_121701_37_2_mi_W_of_Westmorland_3_5.pdf
July 05, 2020 314.08 KB
1638_2020-06-29_015549_61_5_mi_N_of_Ridgecrest_3_5.pdf
June 29, 2020 292.65 KB
1637_2020-06-28_221358_12_8_mi_NW_of_Calipatria_3_2.pdf
June 28, 2020 308.22 KB
1636_post_event_summary.pdf
June 25, 2020 109.77 KB
1635_2020-06-25_040907_13_2_mi_NE_of_Healdsburg_3_4.pdf
June 25, 2020 321.00 KB
1634_2020-06-24_211248_61_5_mi_N_of_Ridgecrest_3_7.pdf
June 24, 2020 292.71 KB
1633_2020-06-24_182038_61_6_mi_N_of_Ridgecrest_3_7.pdf
June 24, 2020 292.32 KB
1632_2020-06-24_175919_59_4_mi_N_of_Ridgecrest_4_4.pdf
June 24, 2020 323.94 KB
1631_2020-06-24_174049_59_8_mi_N_of_Ridgecrest_6_0.pdf
June 24, 2020 295.50 KB
1630_2020-06-23_025158_59_6_mi_N_of_Ridgecrest_3_8.pdf
June 23, 2020 293.50 KB
1629_2020-06-23_003052_59_6_mi_N_of_Ridgecrest_3_6.pdf
June 23, 2020 291.32 KB
1628_2020-06-23_002546_59_6_mi_N_of_Ridgecrest_4_4.pdf
June 23, 2020 326.30 KB
1627_2020-06-17_173502_8_0_mi_E_of_Milpitas_3_6.pdf
June 17, 2020 374.88 KB
1626_2020-06-16_055822_30_0_mi_N_of_Ridgecrest_3_8.pdf
June 16, 2020 297.70 KB
1625_2020-06-11_041412_14_6_mi_N_of_Ridgecrest_3_6.pdf
June 11, 2020 285.99 KB
1624_2020-06-10_132546_9_3_mi_S_of_Hollister_3_5.pdf
June 10, 2020 339.06 KB
1622_2020-06-07_034204_40_4_mi_NW_of_Ridgecrest_3_6.pdf
June 09, 2020 302.15 KB
1623_2020-06-08_041505_14_1_mi_E_of_Ridgecrest_4_3.pdf
June 08, 2020 275.38 KB
1621_2020-06-04_102728_14_1_mi_E_of_Ridgecrest_3_5.pdf
June 04, 2020 272.00 KB
1619_2020-06-04_022754_40_4_mi_NW_of_Ridgecrest_4_2.pdf
June 04, 2020 321.52 KB
1618_post_event_summary.pdf
June 04, 2020 305.03 KB
1617_2020-06-04_022729_14_4_mi_E_of_Ridgecrest_1_6.pdf
June 04, 2020 259.38 KB
1616_2020-06-04_013211_13_6_mi_E_of_Ridgecrest_5_1.pdf
June 04, 2020 290.26 KB
1615_2020-06-03_043623_24_9_mi_N_of_Barstow_4_0.pdf
June 03, 2020 276.73 KB
1614_2020-06-02_053931___8_4_mi_W_of_Calipatria_2_9.pdf
June 02, 2020 303.02 KB
1613_2020-05-31_010715__30_6_mi_NE_of_Mammoth_Lakes_4_4.pdf
May 31, 2020 296.24 KB
1612_2020-05-30_092257__31_1_mi_NE_of_Mammoth_Lakes_3_5.pdf
May 30, 2020 285.82 KB
1611_2020-05-28_191913__13_4_mi_NE_of_Gonzales_3_7.pdf
May 28, 2020 332.01 KB