AAVSO Sudden Ionospheric Disturbance Report August 2025 Observers: A118 A119 A131 A136 A138 A141 A148 A152 A153 A154 A96 A97 YYMMDD Event Peak Importance 250801 1235 2+ 250801 1819 2 250801 2132 1- 250802 1110 2 250802 1453 1- A148 - XRA 250802 1500 2+ A118 - XRA 250802 1740 1- 250802 1802 1- A148 - XRA 250802 1919 2 250803 0907 1 A131 - XRA 250803 0929 1+ 250803 1250 2 A118 - XRA 250803 1356 2 250803 1403 2 A148 - XRA 250803 1409 2 A148 - XRA 250803 1512 2+ A118 - XRA 250803 1715 1+ 250803 1931 1- A153 - XRA 250803 2154 2+ 250804 0131 2 A153 - XRA 250804 0511 2+ 250804 1052 2+ 250804 1502 2+ A136 - XRA 250805 1553 2 250805 1557 2 250805 1720 1+ 250805 1941 1+ 250805 2052 1+ 250805 2259 1- A148 - XRA 250806 0614 1- 250806 0751 1 250806 1045 1 250806 1105 1+ 250806 1151 2 250806 1329 2 250806 1454 1- 250806 1603 1 250806 1705 2 250806 2112 1+ 250807 0000 3+ A154 - FLA 250807 0958 1+ 250807 1050 1+ A131 - QUAL 250807 1111 2 250807 1125 3 250807 1130 2+ 250807 1447 2 250807 2044 2 250808 0848 2 250808 1436 2+ 250808 1444 2+ 250808 1514 2 A152 - QUAL 250808 1657 2 250808 1759 1 250808 1809 2 250808 1910 1+ 250808 2123 2 A153 - XRA 250808 2219 1 250809 0633 1 A131 - XRA 250809 0702 2 250809 0812 1+ 250809 0915 2+ A131 - QUAL 250809 1048 2 250809 1147 1+ 250809 1220 1- 250809 1252 1- 250809 1315 1 250809 1552 1 250809 1620 1 250809 1641 1 250809 1849 1 A97 - XRA 250810 1212 2+ 250810 1509 2+ 250810 2306 2+ A138 - XRA 250811 0537 1 250811 0612 1+ 250811 0842 2+ 250811 1038 1+ 250811 1054 2 250811 1146 2 250811 1239 2+ 250811 1358 1+ 250811 1431 2+ 250811 1437 2 250811 1533 2+ 250811 2027 1 250812 0056 2+ A153 - XRA 250812 0640 1+ 250812 0845 1 250812 1038 2+ A118 - QUAL 250812 1152 1- 250812 1215 2 250812 1255 1 250812 1622 1+ 250812 1842 2+ 250813 1820 1 A97 - XRA 250813 2005 1 A131 - XRA 250815 0905 1+ A136 - XRA 250815 0943 1+ 250815 1039 2 250815 1147 2 250815 1248 1+ 250815 2123 1+ 250815 2149 3+ A141 - QUAL 250816 1853 1 A97 - QUAL 250816 2101 2 A153 - XRA 250817 1959 2 250820 0742 2+ A119 - QUAL 250821 1554 1 A97 - XRA 250822 1815 2 A148 - QUAL 250822 1829 3 A148 - QUAL 250822 1850 2+ 250823 1331 2 250823 1453 2 250823 1516 1- A131 - XRA 250823 1921 2 250823 2004 2 250823 2258 2 A148 - XRA 250824 0705 1 250824 0742 1 250824 0832 2 250824 1411 2 A131 - QUAL 250825 0526 3 A136 - XRA 250825 0532 3 A131 - XRA 250825 0857 2 250825 1043 2 250825 1246 1 A118 - XRA 250825 1518 1+ 250825 1537 2 250825 1629 3+ A153 - XRA 250825 1654 1+ 250826 0031 2+ A153 - XRA 250826 0529 2+ 250826 0825 1 A131 - FLA 250826 0858 1- A131 - QUAL 250826 1214 1 A131 - FLA 250826 1312 1+ 250826 1341 2 A148 - QUAL 250826 1400 2+ 250827 1248 2+ 250827 1253 2+ 250827 1433 1 250827 1958 2 A148 - FLA 250828 0931 1+ A131 - QUAL 250828 1037 1+ 250828 1133 1+ A131 - QUAL 250828 1328 1 A131 - QUAL 250828 1407 1- 250828 1416 2 250828 1433 2+ A138 - QUAL 250828 1519 1- A131 - XRA 250828 1712 1+ 250828 1902 1 250828 2042 2 250828 2158 1+ A138 - XRA 250828 2246 2 A138 - XRA 250829 0622 1+ A131 - XRA 250829 0857 1- A131 - XRA 250829 1142 1- A131 - FLA 250829 1233 1- 250829 1245 1 250829 1317 1- A131 - FLA 250829 1417 1- A131 - QUAL 250829 1717 2 250830 0550 1+ A131 - XRA 250830 1038 1+ 250830 1412 2 250830 1420 2+ 250830 1558 2 250830 1622 3+ A138 - QUAL 250830 1931 3 250830 1948 2+ 250830 1957 2+ 250831 1825 2+ 250831 1826 2+ ************************************************** Importance Summary - Aug 2025 1- events: 20 1 events: 29 1+ events: 32 2 events: 50 2+ events: 34 3 events: 5 3+ events: 4 ------------------ Total events: 174