Aurora & Space WeatherHome › Geomagnetic history › 1939
Geomagnetic storm on 4 Oct 1939 (G3)
Max Kp7+G3
Ap51No. 21 in 1939
Consecutive G1+ days2
Ap rank856since 1932
Kp by 3-hour slot (UTC)
7+
7+
4-
3o
4o
3-
3+
2-
The days around it
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Oct 1939 | 3+ | 8 | – |
| 2 Oct 1939 | 2o | 5 | – |
| 3 Oct 1939 | 6- | 38 | G2 |
| 4 Oct 1939 | 7+ | 51 | G3 |
| 5 Oct 1939 | 4+ | 15 | – |
| 6 Oct 1939 | 6+ | 32 | G2 |
| 7 Oct 1939 | 5- | 14 | G1 |
Highest-Ap days of 1939
135
133
94
92
89
89
88
79
74
73
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 51: No. 856 of 34,615 days since 1932 by Ap.