Aurora & Space WeatherHome › Geomagnetic history › 1999
Geomagnetic storm on 22 Oct 1999 (G4)
Max Kp8oG4
Ap91No. 1 in 1999
Consecutive G1+ days4
Ap rank212since 1932
Kp by 3-hour slot (UTC)
7o
8-
8o
5+
5-
4+
6-
3+
The days around it
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 19 Oct 1999 | 3o | 6 | – |
| 20 Oct 1999 | 1o | 3 | – |
| 21 Oct 1999 | 5o | 20 | G1 |
| 22 Oct 1999 | 8o | 91 | G4 |
| 23 Oct 1999 | 5+ | 32 | G1 |
| 24 Oct 1999 | 5- | 26 | G1 |
| 25 Oct 1999 | 4- | 16 | – |
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 8o, Ap 91: No. 212 of 34,615 days since 1932 by Ap.