AAVSO Sudden Ionospheric Disturbance Report February 1999 Observers: A-40 A-50 A-52 A-62 A-72 A-80 A-82 A-84 A-90 A-91 YYMMDD Event Peak (UT) Importance 990201 0841 2 990204 0640 2 990208 0850 2 990208 1615 1- 990209 0505 1+ 990210 0916 1+ 990212 0720 1 990212 0823 2 990212 0955 1+ 990212 1050 1- 990212 1355 2 990212 1535 1+ 990213 0727 2 990213 1215 2 990213 1528 1- 990213 1615 2+ 990214 0657 1 990214 0935 1 990214 1042 2+ 990214 1425 1+ 990215 0927 1+ 990215 1641 2 990215 1839 1 990215 1907 1 990216 0016 1+ 990216 0410 1+ 990216 1740 2+ 990216 1934 2 990216 2124 2 990217 2031 2 990218 1015 1 990218 1235 1 990218 1718 1- 990219 1625 1 990220 0407 2 990220 1522 1+ 990221 0948 2+ 990221 1330 2+ 990221 2235 1 990222 1300 3 990225 1025 1- 990225 1046 1- 990225 1756 1 990227 0857 1 990228 1641 2+ 990228 1930 1+ 990228 2140 1+ ******************************************* Importance Summary February 1999 1- events: 6 1 events: 11 1+ events: 11 2 events: 12 2+ events: 6 3 events: 1 3+ events: 0 Total events: 47