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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
1546_2020-02-02_005950__14_7_mi_SE_of_Hemet_3_7.pdf
February 02, 2020 367.12 KB
1545_2020-02-01_183654___9_4_mi_E_of_Mammoth_Lakes_4_7.pdf
February 01, 2020 335.77 KB
1544_2020-01-31_074537__21_6_mi_SE_of_Mexicali_B_C__3_1.pdf
January 31, 2020 281.98 KB
1543_2020-01-29_123050___8_2_mi_N_of_Ukiah_3_5.pdf
January 29, 2020 298.60 KB
1542_2020-01-25_030335__14_2_mi_N_of_Barstow_4_5.pdf
January 25, 2020 297.08 KB
1541_2020-01-24_213533__48_0_mi_S_of_Port_Alberni_4_5.pdf
January 24, 2020 232.02 KB
1540_2020-01-22_085256__20_1_mi_SE_of_Mexicali_B_C__3_4.pdf
January 22, 2020 283.77 KB
1539_2020-01-22_074110___3_1_mi_NW_of_San_Fernando_3_6.pdf
January 22, 2020 336.86 KB
1538_2020-01-12_052103__21_8_mi_SE_of_Mexicali_B_C__4_0.pdf
January 12, 2020 295.44 KB
1537_2020-01-02_101300__17_7_mi_S_of_Port_Hueneme_3_7.pdf
January 02, 2020 273.10 KB
1536_2020-01-02_071631___5_8_mi_NE_of_Morgan_Hill_4_1.pdf
January 02, 2020 350.85 KB
1534_2019-12-26_194823___9_3_mi_SE_of_Mammoth_Lakes_4_0.pdf
December 26, 2019 305.95 KB
1533_2019-12-26_041200__28_6_mi_NE_of_Ridgecrest_3_2.pdf
December 26, 2019 270.91 KB
1532_2019-12-25_231506__46_7_mi_SW_of_Avalon_3_4.pdf
December 25, 2019 181.03 KB
1531_2019-12-25_230727__35_2_mi_N_of_Ridgecrest_2_5.pdf
December 25, 2019 296.55 KB
1530_2019-12-24_063359__12_2_mi_SW_of_Clearlake_3_3.pdf
December 24, 2019 307.73 KB
1529_2019-12-21_082432__12_2_mi_E_of_Ridgecrest_4_0.pdf
December 21, 2019 272.39 KB
1527_2019-12-17_182921___7_7_mi_SE_of_Parkfield_4_4.pdf
December 21, 2019 320.08 KB
1528_2019-12-19_153013__20_2_mi_SW_of_Rio_Dell_3_9.pdf
December 19, 2019 215.55 KB
1526_2019-12-17_065745___8_5_mi_NE_of_Ridgecrest_3_5.pdf
December 17, 2019 278.32 KB
1525_2019-12-16_221558___8_7_mi_E_of_Ridgecrest_3_5.pdf
December 16, 2019 276.98 KB
1524_2019-12-12_111340___9_1_mi_NE_of_Ridgecrest_3_5.pdf
December 12, 2019 277.51 KB
1522_2019-12-10_220647__43_5_mi_W_of_Coronado_3_4.pdf
December 11, 2019 195.07 KB
1523_2019-12-11_024820__76_1_mi_SE_of_Tijuana_B_C__4_2.pdf
December 11, 2019 209.04 KB
1521_2019-12-05_085531___5_9_mi_NE_of_Ridgecrest_3_9.pdf
December 05, 2019 283.67 KB
1520_2019-11-30_045826__27_6_mi_N_of_Gold_Beach_3_4.pdf
November 30, 2019 214.75 KB
1519_2019-11-30_014511__27_9_mi_N_of_Gold_Beach_4_6.pdf
November 30, 2019 229.78 KB
1518_2019-11-29_004942___8_5_mi_NE_of_Ridgecrest_3_7.pdf
November 29, 2019 279.58 KB
1517_2019-11-28_231059__20_3_mi_N_of_Adelanto_3_6.pdf
November 28, 2019 304.27 KB
1516_2019-11-26_000603__18_5_mi_E_of_Ridgecrest_3_5.pdf
November 26, 2019 269.84 KB
1515_2019-11-15_222948__12_2_mi_E_of_Cloverdale_3_5.pdf
November 21, 2019 305.78 KB
1514_2019-11-13_192653__14_9_mi_E_of_Ridgecrest_4_0.pdf
November 15, 2019 269.75 KB
1513_2019-11-12_104401__17_7_mi_N_of_Point_Arena_3_2.pdf
November 12, 2019 263.56 KB
1512_2019-11-12_021352___0_9_mi_E_of_El_Centro_4_0.pdf
November 12, 2019 288.49 KB
1511_2019-11-12_020704___1_0_mi_E_of_El_Centro_3_0.pdf
November 12, 2019 285.53 KB
1510_2019-11-10_220759__10_2_mi_N_of_Indio_3_5.pdf
November 10, 2019 331.82 KB
1509_2019-11-08_132939___4_0_mi_W_of_Ventura_3_6.pdf
November 08, 2019 290.47 KB
1508_2019-11-08_121012___3_6_mi_W_of_Ventura_3_5.pdf
November 08, 2019 287.55 KB
1507_2019-11-07_130539___3_8_mi_W_of_Ventura_3_4.pdf
November 07, 2019 288.96 KB
1506_2019-11-07_093152___7_7_mi_W_of_Calipatria_2_5.pdf
November 07, 2019 307.71 KB
1483_2019-10-01_131108___9_4_mi_NE_of_Ridgecrest_3_6.pdf
November 06, 2019 280.30 KB
1505_2019-11-03_203457__12_6_mi_NE_of_Healdsburg_3_9.pdf
November 03, 2019 308.90 KB
1504_2019-11-02_140550__12_2_mi_E_of_Cloverdale_3_6.pdf
November 02, 2019 309.21 KB
1503_2019-11-01_093317__59_5_mi_SE_of_Bishop_3_6.pdf
November 01, 2019 287.72 KB
1502_2019-10-29_162132__21_2_mi_E_of_Escondido_3_6.pdf
October 29, 2019 356.21 KB
1501_2019-10-29_152116__13_8_mi_NE_of_Gonzales_4_0.pdf
October 29, 2019 319.88 KB
1500_2019-10-29_093412__13_8_mi_NE_of_Gonzales_3_5.pdf
October 29, 2019 319.78 KB
1499_2019-10-29_010038___8_8_mi_E_of_Blue_Lake_3_4.pdf
October 29, 2019 288.04 KB
1498_2019-10-28_110110__72_9_mi_W_of_Brookings_4_4.pdf
October 28, 2019 148.39 KB
1497_2019-10-28_081043__13_0_mi_E_of_Cloverdale_3_3.pdf
October 28, 2019 307.20 KB