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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
2166_2023-04-29_21:06:47_3.2_mi_NW_of_Calexico_3.7.pdf
April 29, 2023 282.53 KB
2165_2023-04-29_12:07:03_3.8_mi_NW_of_Calexico_4.0.pdf
April 29, 2023 283.07 KB
2164_2023-04-28_03:40:16_2.3_mi_NW_of_Calexico_1.9.pdf
April 28, 2023 260.59 KB
2162_2023-04-17_15:27:56_17.4_mi_E_of_Barstow_3.4.pdf
April 17, 2023 261.97 KB
2161_2023-04-17_07:45:18_49.0_mi_SW_of_Goleta_3.7.pdf
April 17, 2023 217.17 KB
2160_2023-04-14_14:56:56_13.1_mi_SW_of_Mexicali_B.C._3.7.pdf
April 14, 2023 262.21 KB
2159_2023-04-13_07:42:10_12.6_mi_NE_of_Healdsburg_3.8.pdf
April 13, 2023 307.00 KB
2158_2023-04-13_07:38:45_13.3_mi_NE_of_Healdsburg_3.0.pdf
April 13, 2023 283.83 KB
2157_2023-04-13_03:00:25_11.4_mi_W_of_Ukiah_2.6.pdf
April 13, 2023 226.70 KB
2155_2023-04-12_05:39:51_11.5_mi_E_of_Cloverdale_4.1.pdf
April 12, 2023 320.21 KB
2154_2023-04-12_02:22:35_16.3_mi_E_of_Gonzales_3.3.pdf
April 12, 2023 291.41 KB
2153_2023-04-09_02:06:52_13.2_mi_SW_of_Mexicali_B.C._3.6.pdf
April 09, 2023 267.32 KB
2152_2023-04-08_21:25:15_10.2_mi_E_of_Cloverdale_3.1.pdf
April 08, 2023 269.16 KB
2151_2023-04-08_05:07:58_11.4_mi_E_of_Cloverdale_3.3.pdf
April 08, 2023 276.24 KB
2150_2023-04-05_11:31:54_93.2_mi_W_of_Eureka_2.9.pdf
April 05, 2023 165.08 KB
2149_2023-04-04_22:23:17_5.6_mi_SE_of_Hollister_4.7.pdf
April 04, 2023 345.96 KB
2148_2023-04-02_21:31:03_77.0_mi_S_of_Tijuana_B.C._3.9.pdf
April 02, 2023 194.95 KB
2147_2023-04-02_11:44:21_29.8_mi_SW_of_Fortuna_2.8.pdf
April 02, 2023 182.45 KB
2146_2023-04-01_16:43:33_2.1_mi_N_of_San_Leandro_3.2.pdf
April 01, 2023 360.91 KB
2145_2023-04-01_01:16:07_16.0_mi_SE_of_Temecula_4.5.pdf
April 01, 2023 350.94 KB
2144_2023-03-28_13:01:18_0.5_mi_NE_of_Pacifica_3.5.pdf
March 28, 2023 347.01 KB
2143_2023-03-23_03:38:53_11.4_mi_S_of_Hollister_3.4.pdf
March 23, 2023 285.53 KB
2142_2023-03-21_23:18:19_10.0_mi_SW_of_Fortuna_4.6.pdf
March 21, 2023 251.94 KB
2141_2023-03-18_17:19:33_17.5_mi_NW_of_Westmorland_3.4.pdf
March 18, 2023 243.06 KB
2140_2023-03-18_16:52:07_17.7_mi_NW_of_Westmorland_3.4.pdf
March 18, 2023 243.82 KB
2139_2023-03-18_14:23:06_25.1_mi_NE_of_Bishop_3.9.pdf
March 18, 2023 266.39 KB
2138_2023-03-18_07:03:42_26.1_mi_NE_of_Bishop_3.9.pdf
March 18, 2023 278.11 KB
2137_2023-03-15_18:29:41_32.7_mi_S_of_King_City_3.7.pdf
March 15, 2023 252.02 KB
2136_2023-03-14_19:15:55_11.9_mi_S_of_Hollister_3.0.pdf
March 14, 2023 288.76 KB
2135_2023-03-14_17:41:44_11.4_mi_S_of_Hollister_3.4.pdf
March 14, 2023 292.67 KB
2134_2023-03-14_10:13:19_25.3_mi_NE_of_Bishop_3.9.pdf
March 14, 2023 270.87 KB
2133_2023-03-14_05:00:29_25.2_mi_NE_of_Bishop_4.0.pdf
March 14, 2023 273.17 KB
2132_2023-03-10_06:50:29_23.5_mi_SE_of_Mexicali_B.C._2.4.pdf
March 10, 2023 221.03 KB
2131_2023-03-07_14:33:12_14.8_mi_NE_of_Gonzales_3.9.pdf
March 07, 2023 302.79 KB
2130_2023-03-02_21:16:50_12.7_mi_E_of_Cloverdale_3.6.pdf
March 02, 2023 312.23 KB
2129_2023-03-02_21:16:17_13.0_mi_E_of_Cloverdale_3.4.pdf
March 02, 2023 292.59 KB
2128_2023-03-01_07:09:40_11.1_mi_E_of_Cloverdale_3.4.pdf
March 01, 2023 290.70 KB
2127_2023-02-28_03:36:34_11.0_mi_E_of_Cloverdale_2.9.pdf
February 28, 2023 280.71 KB
2126_2023-02-22_20:01:57_8.9_mi_E_of_Cloverdale_3.2.pdf
February 22, 2023 277.60 KB
2125_2023-02-09_17:43:05_13.5_mi_SW_of_Clearlake_2.8.pdf
February 09, 2023 312.57 KB
2124_2023-02-09_10:13:20_22.2_mi_E_of_Arroyo_Grande_2.6.pdf
February 09, 2023 275.61 KB
2123_2023-02-06_09:53:42_17.7_mi_W_of_Fortuna_2.9.pdf
February 06, 2023 210.29 KB
2122_2023-02-02_00:11:01_2.3_mi_NW_of_San_Fernando_2.9.pdf
February 02, 2023 357.80 KB
2121_2023-01-28_23:56:59_11.4_mi_SW_of_Fortuna_3.8.pdf
January 29, 2023 226.72 KB
2120_2023-01-27_10:28:22_2.1_mi_SE_of_Fortuna_3.7.pdf
January 27, 2023 266.66 KB
2119_2023-01-25_10:03:33_10.1_mi_SE_of_Malibu_3.5.pdf
January 25, 2023 309.23 KB
2118_2023-01-25_10:00:54_10.4_mi_SE_of_Malibu_4.2.pdf
January 25, 2023 312.64 KB
2117_2023-01-23_13:58:02_7.7_mi_N_of_Gilroy_3.7.pdf
January 23, 2023 359.04 KB
2116_2023-01-21_03:27:50_12.4_mi_E_of_Cloverdale_3.3.pdf
January 21, 2023 316.36 KB
2115_2023-01-20_08:01:14_14.7_mi_E_of_Trinidad_4.2.pdf
January 20, 2023 286.08 KB