Aurora & Space WeatherHome › Geomagnetic history › 1987
Geomagnetic activity in October 1987
Mean Ap15.6No. 316 of 1138
G1+ days10
G3+ days0
Max Ap4428 Oct 1987
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 3 Oct 1987 | 6o | 36 | G2 |
| 11 Oct 1987 | 6- | 28 | G2 |
| 13 Oct 1987 | 5- | 24 | G1 |
| 14 Oct 1987 | 6- | 31 | G2 |
| 15 Oct 1987 | 5- | 26 | G1 |
| 17 Oct 1987 | 5- | 18 | G1 |
| 24 Oct 1987 | 5+ | 19 | G1 |
| 25 Oct 1987 | 5+ | 28 | G1 |
| 27 Oct 1987 | 5+ | 35 | G1 |
| 28 Oct 1987 | 6- | 44 | G2 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| October 1986 | 10.5 | 5 | 1 |
| October 1987 | 15.6 | 10 | 0 |
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.
← September 1987November 1987 →
About this page
Mean Ap 15.6 in October 1987, No. 316 of 1138 months since 1932; 10 days reached G1 or higher.