Aurora & Space WeatherHome › Geomagnetic history › 1999
Geomagnetic storm on 17 Apr 1999 (G3)
Max Kp7+G3
Ap47No. 5 in 1999
Consecutive G1+ days2
Ap rank1,096since 1932
Kp by 3-hour slot (UTC)
6o
7+
5+
5o
2+
2+
3-
2-
The days around it
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 14 Apr 1999 | 3o | 7 | – |
| 15 Apr 1999 | 1+ | 4 | – |
| 16 Apr 1999 | 5o | 18 | G1 |
| 17 Apr 1999 | 7+ | 47 | G3 |
| 18 Apr 1999 | 3- | 6 | – |
| 19 Apr 1999 | 4- | 12 | – |
| 20 Apr 1999 | 4+ | 24 | – |
Highest-Ap days of 1999
91
80
53
50
47
46
46
43
43
41
Dates and time slots are UTC. Kp is the 3-hourly planetary geomagnetic index (0–9); Ap is the daily average disturbance. G1–G5 follow the NOAA storm scale (Kp 5- and above counted as G1). Aurora visibility also depends on weather and location. The latest values are preliminary.
About this page
Max Kp 7+, Ap 47: No. 1,096 of 34,615 days since 1932 by Ap.