AAVSO Sudden Ionospheric Disturbance Report April 2025 Observers: A118 A119 A138 A141 A148 A150 A152 A153 A154 A96 A97 YYMMDD Event Peak Importance 250401 0645 1+ 250401 0755 1 250401 1041 1 250401 1653 1+ 250401 1845 1+ 250401 1939 1+ 250401 2057 2 250401 2207 1 250401 2225 1+ 250401 2228 1+ 250402 1053 2 250402 1128 2 250402 1432 1- A96 - XRA 250402 2019 1 A148 - XRA 250403 0824 1- A96 - XRA 250403 0915 1- A96 - XRA 250404 1025 2 A96 - XRA 250404 1326 1- A97 - XRA 250404 1446 1 250404 2339 1+ A148 - XRA 250405 0713 1- A96 - XRA 250405 1902 1- 250405 2009 2 250406 1557 1 A148 - XRA 250406 1957 1- A148 - XRA 250407 0647 1- A96 - XRA 250407 1504 1- A118 - XRA 250407 1535 1 250407 1542 1- A148 - XRA 250407 1615 3 A141 - QUAL 250407 1751 1- A148 - XRA 250407 2019 1- A148 - XRA 250408 1359 1- A148 - XRA 250408 1945 1- 250408 2057 1 250408 2223 2 250409 1231 1- A148 - XRA 250409 1732 1 250410 0753 1- A152 - XRA 250410 1652 2 A97 - XRA 250411 0712 1- 250411 0828 1 250411 0957 1+ A96 - XRA 250411 1215 2+ 250411 1338 1- 250411 1626 1- 250411 1649 1+ 250411 1902 2 250411 2220 2+ 250412 0000 3+ A154 - FLA 250412 0548 1 250412 0720 1- 250412 0749 1 250412 0803 1 250412 1006 1- 250412 1025 1 250412 1116 1+ 250412 1143 1 250412 1202 1+ A118 - QUAL 250412 1242 2 250412 1434 1 250412 1514 2 250412 1945 1+ 250412 2055 1+ 250412 2158 3 A148 - QUAL 250413 0652 2 250413 0758 1- A118 - QUAL 250413 0818 2 250413 0953 2 250413 0957 2 250413 1013 1 A152 - XRA 250413 1115 3 A118 - QUAL 250413 1318 1 A118 - QUAL 250413 1402 2 250413 1508 1 250413 1541 2 250413 1547 2 250413 1852 2 250413 2042 1 A148 - XRA 250413 2205 2+ 250414 0603 1 250414 0650 2 250414 1231 2+ 250414 1451 1 250414 1542 1+ 250414 1844 2+ 250414 1956 1+ 250414 2242 1 A148 - XRA 250415 0814 1+ A118 - QUAL 250415 0844 1+ 250415 0933 2 250415 1020 2 250415 1348 1- A96 - XRA 250415 1548 1- A97 - QUAL 250415 1807 2 250415 2018 1+ A148 - XRA 250415 2117 1+ A153 - FLA 250417 0945 1+ A118 - XRA 250417 1225 2 A118 - QUAL 250417 1420 2+ 250418 2342 2+ A148 - XRA 250418 2349 2 A138 - XRA 250419 1157 2 A118 - QUAL 250419 1630 1- 250420 1159 2+ 250420 1208 3 250420 1716 1+ 250421 0000 1 A141 - QUAL 250421 1836 1 250422 1040 3 250422 1047 3 250422 1858 1- 250423 1453 1- 250424 1438 1+ A97 - XRA 250424 1543 1- A97 - XRA 250427 1649 2+ A150 - QUAL 250427 1724 1- A97 - XRA 250427 1848 1+ A148 - XRA 250427 2244 1- A148 - XRA 250428 2154 1+ 250429 0515 1+ 250429 1003 2 250429 1059 2+ 250429 1212 1- 250429 1342 1+ A97 - QUAL 250429 1506 2 250429 1506 1+ 250429 2322 1 250429 2322 1 250430 0751 2 250430 0754 1 250430 1533 1+ A118 - XRA 250430 1533 1+ A118 - XRA ************************************************** Importance Summary - Apr 2025 1- events: 31 1 events: 28 1+ events: 29 2 events: 28 2+ events: 10 3 events: 6 3+ events: 1 ------------------ Total events: 133