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Geomagnetic activity in April 1971
Mean Ap15.0No. 359 of 1138
G1+ days10
G3+ days2
Max Ap539 Apr 1971
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Apr 1971 | 5- | 12 | G1 |
| 4 Apr 1971 | 5+ | 27 | G1 |
| 9 Apr 1971 | 6o | 53 | G2 |
| 10 Apr 1971 | 5+ | 30 | G1 |
| 11 Apr 1971 | 5o | 27 | G1 |
| 14 Apr 1971 | 8- | 39 | G4 |
| 15 Apr 1971 | 7- | 36 | G3 |
| 21 Apr 1971 | 6+ | 22 | G2 |
| 22 Apr 1971 | 5- | 14 | G1 |
| 28 Apr 1971 | 5o | 21 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| April 1970 | 15.6 | 8 | 2 |
| April 1971 | 15.0 | 10 | 2 |
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
Mean Ap 15.0 in April 1971, No. 359 of 1138 months since 1932; 10 days reached G1 or higher.