AAVSO Sudden Ionospheric Disturbance Report July 1999 Observers: A-50 A-52 A-62 A-72 A-81 A-83 A-84 A-87 A-90 YYMMDD Event Peak (UT) Importance 990701 0710 2 990701 0810 1+ 990701 1257 2+ 990701 1350 2 990701 1457 2+ 990701 1534 1+ 990701 1658 1- 990701 1743 2+ 990701 2143 2+ 990702 0719 2 990702 1521 2+ 990703 1507 1+ 990703 1854 1+ 990703 1903 2+ 990703 2022 2 990703 2048 2 990703 2123 2 990704 0826 2+ 990704 1617 2+ 990704 1859 2 990704 2026 1+ 990704 2045 1+ 990704 2328 2+ 990705 0131 2 990705 1202 2 990705 1718 2+ 990705 1846 2+ 990705 1902 1+ 990707 1530 2 990708 0657 2+ 990708 0928 1 990709 1800 1 990709 1856 1+ 990709 1959 1 990709 2019 1- 990709 2341 2+ 990711 1317 1 990711 1551 1+ 990712 0730 1- 990715 1436 1+ 990715 1558 1- 990716 0846 2+ 990716 1549 2+ 990716 1746 2+ 990717 1404 1+ 990717 1627 2 990717 1746 2+ 990717 2207 1 990718 0745 2 990718 1754 2+ 990718 1852 2+ 990719 0835 3 990719 1948 1+ 990720 0607 1 990720 0823 1- 990721 0812 1 990721 1845 2 990722 2107 2+ 990723 0504 1+ 990723 0912 1 990723 1244 2 990723 1400 2 990723 1600 2 990723 2000 3 990723 2106 2 990723 2300 2 990724 0403 1+ 990724 0753 2+ 990724 1125 2 990724 1448 2 990724 1619 2+ 990724 2045 2+ 990724 2245 2 990725 0104 1- 990725 0132 1+ 990725 0513 1 990725 1335 3 990725 1842 2 990727 1827 2 990727 1901 1 990728 0810 2+ 990728 1807 3 990728 1936 2+ 990728 2041 1+ 990728 2236 2+ 990729 1253 2 990729 1447 1+ 990729 1515 2 990729 1648 2 990729 1730 2 990729 1915 1 990729 1935 2+ 990729 2345 2 990730 0114 1+ 990730 0600 1- 990730 0720 1 990730 0855 1+ 990730 1421 2 990730 1520 2+ 990730 1606 1+ 990730 1706 1- 990730 1732 2 990730 1820 3 990730 1852 1 990730 1915 2 990730 1946 3 990730 2021 2 990730 2157 2 990730 2335 2+ 990731 1030 1 990731 1400 1+ 990731 1614 2 990731 1800 2 990731 1837 2 990731 2359 1+ ******************************************* Importance Summary July 1999 1- events: 8 1 events: 14 1+ events: 22 2 events: 36 2+ events: 29 3 events: 6 3+ events: 0 Total events: 115