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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
1696_2020-10-04_044917_6_2_mi_SE_of_Willits_3_5.pdf
October 04, 2020 310.05 KB
1695_2020-10-02_021044_3_2_mi_NE_of_Westmorland_2_6.pdf
October 02, 2020 299.60 KB
1694_2020-10-01_224731_2_8_mi_NE_of_Westmorland_3_5.pdf
October 01, 2020 298.56 KB
1688_2020-10-01_005813_2_5_mi_NE_of_Westmorland_4_1.pdf
October 01, 2020 304.37 KB
1693_2020-10-01_144642_3_1_mi_NE_of_Westmorland_3_6.pdf
October 01, 2020 297.90 KB
1692_2020-10-01_125441_2_9_mi_NE_of_Westmorland_2_7.pdf
October 01, 2020 301.29 KB
1691_2020-10-01_034016_2_7_mi_N_of_Westmorland_3_5.pdf
October 01, 2020 301.11 KB
1690_2020-10-01_033634_2_5_mi_NE_of_Westmorland_4_0.pdf
October 01, 2020 306.73 KB
1689_2020-10-01_033059_1_5_mi_SW_of_Calipatria_3_5.pdf
October 01, 2020 297.26 KB
1687_2020-10-01_004118_2_7_mi_NE_of_Westmorland_3_8.pdf
October 01, 2020 303.74 KB
1686_2020-10-01_003127_2_2_mi_NE_of_Westmorland_4_6.pdf
October 01, 2020 303.63 KB
1685_2020-09-30_235802_2_7_mi_E_of_Westmorland_3_5.pdf
October 01, 2020 302.00 KB
1684_2020-09-30_233152_2_1_mi_NE_of_Westmorland_3_9.pdf
September 30, 2020 303.33 KB
1683_2020-09-30_230602_1_9_mi_E_of_Westmorland_3_5.pdf
September 30, 2020 300.50 KB
1682_2020-09-29_160230_6_2_mi_NE_of_Milpitas_3_3.pdf
September 29, 2020 382.57 KB
1681_2020-09-29_155007_21_1_mi_SW_of_Rio_Dell_2_6.pdf
September 29, 2020 218.72 KB
1680_2020-09-28_051636_6_2_mi_NE_of_Milpitas_3_4.pdf
September 28, 2020 382.07 KB
1679_2020-09-25_171011_6_3_mi_E_of_Desert_Hot_Springs_3_6.pdf
September 25, 2020 338.17 KB
1678_2020-09-24_144227_13_4_mi_NE_of_Healdsburg_3_1.pdf
September 24, 2020 321.52 KB
1677_2020-09-24_101115_12_9_mi_E_of_Cloverdale_2_9.pdf
September 24, 2020 320.41 KB
1676_2020-09-19_063846_2_0_mi_W_of_South_El_Monte_4_6.pdf
September 19, 2020 366.00 KB
1675_2020-09-17_183625_13_2_mi_SW_of_Clearlake_2_9.pdf
September 17, 2020 322.59 KB
1674_2020-09-14_153659_31_1_mi_N_of_Willits_3_4.pdf
September 14, 2020 320.06 KB
1673_2020-09-11_081410_58_8_mi_N_of_Ridgecrest_3_5.pdf
September 11, 2020 294.03 KB
1672_2020-09-11_075545_59_3_mi_N_of_Ridgecrest_4_0.pdf
September 11, 2020 296.74 KB
1671_2020-09-10_040057_6_6_mi_SE_of_Willits_2_7.pdf
September 10, 2020 311.38 KB
1670_2020-09-06_014836_5_0_mi_E_of_Solvang_3_8.pdf
September 06, 2020 302.99 KB
1659_2020-08-17_153033_77_9_mi_S_of_Mexicali_B_C__5_1.pdf
September 04, 2020 187.85 KB
1669_2020-09-02_161831_29_4_mi_N_of_Ridgecrest_3_6.pdf
September 02, 2020 292.24 KB
1668_2020-08-29_080606_29_0_mi_N_of_Ridgecrest_3_0.pdf
August 29, 2020 291.86 KB
1667_2020-08-28_112603_13_2_mi_SW_of_Calexico_3_5.pdf
August 28, 2020 278.24 KB
1666_2020-08-27_084831_6_7_mi_SE_of_Willits_3_5.pdf
August 27, 2020 309.06 KB
1665_2020-08-21_082008_12_0_mi_E_of_Ridgecrest_3_7.pdf
August 21, 2020 273.05 KB
1664_2020-08-19_173211_51_3_mi_SW_of_Beatty_4_3.pdf
August 19, 2020 306.47 KB
1663_2020-08-19_015933_6_3_mi_SE_of_Willits_3_8.pdf
August 19, 2020 312.22 KB
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