Aurora & Space WeatherHome › Geomagnetic history › 1999
Geomagnetic storm on 30 Jul 1999 (G4)
Max Kp8-G4
Ap53No. 3 in 1999
Consecutive G1+ days2
Ap rank807since 1932
Kp by 3-hour slot (UTC)
3-
2o
3-
3+
5o
5+
8-
6+
The days around it
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 27 Jul 1999 | 2+ | 5 | – |
| 28 Jul 1999 | 3+ | 9 | – |
| 29 Jul 1999 | 3o | 6 | – |
| 30 Jul 1999 | 8- | 53 | G4 |
| 31 Jul 1999 | 5+ | 28 | G1 |
| 1 Aug 1999 | 4+ | 8 | – |
| 2 Aug 1999 | 2+ | 6 | – |
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 8-, Ap 53: No. 807 of 34,615 days since 1932 by Ap.