Aurora & Space WeatherHome › Geomagnetic history › 1991
Geomagnetic storm on 4 Apr 1991 (G3)
Max Kp7-G3
Ap50No. 36 in 1991
Consecutive G1+ days2
Ap rank931since 1932
Kp by 3-hour slot (UTC)
3+
3-
3-
6+
7-
6-
5o
5-
The days around it
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Apr 1991 | 5- | 29 | G1 |
| 2 Apr 1991 | 4o | 22 | – |
| 3 Apr 1991 | 5+ | 37 | G1 |
| 4 Apr 1991 | 7- | 50 | G3 |
| 5 Apr 1991 | 4o | 15 | – |
| 6 Apr 1991 | 4- | 14 | – |
| 7 Apr 1991 | 3o | 10 | – |
Highest-Ap days of 1991
196
161
134
130
128
120
119
119
117
114
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 50: No. 931 of 34,615 days since 1932 by Ap.