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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
2114_2023-01-20_01:18:07_5.7_mi_SW_of_Cloverdale_3.6.pdf
January 20, 2023 293.20 KB
2113_2023-01-19_20:30:07_14.3_mi_E_of_Trinidad_3.4.pdf
January 19, 2023 279.80 KB
2112_2023-01-19_19:21:41_2.4_mi_S_of_San_Juan_Bautista_3.3.pdf
January 19, 2023 342.49 KB
2111_2023-01-19_17:15:55_2.6_mi_S_of_San_Juan_Bautista_3.8.pdf
January 19, 2023 342.18 KB
2110_2023-01-13_10:02:52_13.0_mi_W_of_Fortuna_3.9.pdf
January 13, 2023 225.64 KB
2109_2023-01-11_17:21:42_41.4_mi_W_of_Fortuna_3.9.pdf
January 11, 2023 166.48 KB
2108_2023-01-10_18:32:14_4.8_mi_NW_of_Blue_Lake_3.5.pdf
January 10, 2023 266.73 KB
2107_2023-01-01_18:35:04_9.3_mi_SE_of_Rio_Dell_4.9.pdf
January 01, 2023 265.72 KB
2106_2023-01-01_06:49:08_13.4_mi_E_of_Gonzales_4.1.pdf
January 01, 2023 321.32 KB
2105_2023-01-01_06:19:31_14.8_mi_NE_of_Gonzales_3.2.pdf
January 01, 2023 320.03 KB
2104_2023-01-01_05:18:17_6.7_mi_N_of_Fortuna_2.9.pdf
January 01, 2023 247.30 KB
2103_2022-12-31_12:12:26_17.8_mi_S_of_La_Quinta_4.2.pdf
December 31, 2022 349.85 KB
2102_2022-12-31_11:41:09_7.8_mi_N_of_Big_Bear_Lake_3.5.pdf
December 31, 2022 326.55 KB
2101_2022-12-24_19:33:44_6.5_mi_NE_of_Rio_Dell_4.2.pdf
December 24, 2022 289.83 KB
2089_2022-12-20_10:34:25_13.4_mi_SW_of_Fortuna_6.1.pdf
December 24, 2022 245.48 KB
2100_2022-12-24_05:13:07_21.2_mi_SW_of_Rio_Dell_3.1.pdf
December 24, 2022 203.06 KB
2099_2022-12-22_08:47:13_13.8_mi_W_of_Fortuna_3.7.pdf
December 22, 2022 221.94 KB
2098_2022-12-22_02:22:50_2.0_mi_NE_of_Union_City_3.3.pdf
December 22, 2022 410.22 KB
2097_2022-12-21_16:28:16_4.6_mi_E_of_Fortuna_3.7.pdf
December 21, 2022 275.31 KB
2096_2022-12-21_01:07:33_19.2_mi_W_of_Fortuna_3.4.pdf
December 21, 2022 203.25 KB
2095_2022-12-20_22:06:34_7.5_mi_SW_of_Fortuna_4.3.pdf
December 20, 2022 241.93 KB
2094_2022-12-20_15:09:05_4.8_mi_E_of_Fortuna_4.0.pdf
December 20, 2022 277.87 KB
2093_2022-12-20_13:53:19_12.6_mi_SW_of_Fortuna_3.5.pdf
December 20, 2022 222.72 KB
2092_2022-12-20_13:35:06_9.4_mi_SW_of_Fortuna_3.8.pdf
December 20, 2022 235.69 KB
2091_2022-12-20_10:52:39_7.5_mi_W_of_Fortuna_3.4.pdf
December 20, 2022 239.56 KB
2090_2022-12-20_10:39:02_3.7_mi_W_of_Rio_Dell_4.6.pdf
December 20, 2022 264.27 KB
2088_2022-12-17_11:39:42_0.7_mi_NE_of_El_Cerrito_3.9.pdf
December 17, 2022 382.60 KB
2087_2022-12-09_05:33:33_12.4_mi_E_of_Cloverdale_2.8.pdf
December 09, 2022 316.16 KB
2086_2022-12-07_14:13:22_26.3_mi_N_of_Tehachapi_3.5.pdf
December 07, 2022 291.17 KB
2085_2022-12-06_00:10:37_8.2_mi_SE_of_Avenal_4.2.pdf
December 06, 2022 295.74 KB
2084_2022-12-05_23:13:16_11.4_mi_E_of_San_Jose_3.7.pdf
December 05, 2022 384.20 KB
2083_2022-12-02_12:21:48_14.4_mi_S_of_Bishop_4.0.pdf
December 02, 2022 327.22 KB
2082_2022-12-01_15:28:29_26.8_mi_W_of_Imperial_4.0.pdf
December 01, 2022 301.46 KB
2081_2022-11-26_03:50:17_68.5_mi_W_of_Port_Alberni_4.8.pdf
November 26, 2022 263.36 KB
2080_2022-11-14_20:27:18_12.4_mi_E_of_Cloverdale_3.1.pdf
November 14, 2022 314.20 KB
2079_2022-11-08_17:35:07_21.1_mi_SW_of_Rio_Dell_2.6.pdf
November 08, 2022 216.15 KB
2078_2022-11-07_05:10:26_77.0_mi_S_of_Mexicali_B.C._3.7.pdf
November 07, 2022 160.85 KB
2077_2022-11-07_04:59:02_77.8_mi_S_of_Mexicali_B.C._4.3.pdf
November 07, 2022 175.47 KB
2076_2022-11-07_02:01:27_13.7_mi_E_of_Willits_3.8.pdf
November 07, 2022 306.61 KB
2075_2022-11-04_20:27:36_12.1_mi_E_of_Cloverdale_2.9.pdf
November 04, 2022 312.40 KB
2074_2022-11-04_20:26:32_12.1_mi_E_of_Cloverdale_3.4.pdf
November 04, 2022 310.81 KB
2073_2022-10-25_22:08:37_12.1_mi_E_of_San_Jose_3.6.pdf
October 25, 2022 369.63 KB
2072_2022-10-25_18:42:02_12.1_mi_E_of_San_Jose_5.0.pdf
October 25, 2022 374.01 KB
2071_2022-10-23_18:16:22_2.2_mi_E_of_Fortuna_4.3.pdf
October 23, 2022 267.05 KB
2070_2022-10-21_18:50:26_11.0_mi_E_of_Cloverdale_2.9.pdf
October 21, 2022 308.13 KB
2069_2022-10-20_07:55:16_32.6_mi_E_of_Rio_Dell_4.1.pdf
October 20, 2022 298.78 KB
2068_2022-10-20_00:02:34_11.2_mi_E_of_Cloverdale_3.4.pdf
October 20, 2022 312.48 KB
2067_2022-10-19_23:59:49_12.2_mi_SW_of_Clearlake_3.4.pdf
October 20, 2022 313.00 KB
2066_2022-10-19_23:59:04_10.9_mi_E_of_Cloverdale_3.5.pdf
October 20, 2022 312.05 KB
2065_2022-10-15_17:30:41_13.5_mi_NE_of_Healdsburg_3.2.pdf
October 15, 2022 319.95 KB