In 1960 the planetary Kp peaked at 9.0 (G5) on 30 April 1960: 155 storm nights over the year, and 16.3% of its three-hour intervals at storm level.
| Month | Max Kp | Peak day | Storm nights | By class | At storm level | Avg Kp |
|---|---|---|---|---|---|---|
| January | 6.3 | 15 | 8 | G1×3G2×5 | 10.1% | 2.5 |
| February | 5.7 | 16 | 11 | G1×10G2×1 | 6.9% | 2.5 |
| March | 8.3 | 31 | 7 | G1×3G2×2G3×1G4×1 | 8.1% | 2.6 |
| April | 9.0 | 30 | 22 | G1×5G2×8G3×7G4×1G5×1 | 32.1% | 3.7 |
| May | 8.3 | 8 | 11 | G1×1G2×5G3×3G4×2 | 14.9% | 3.0 |
| June | 7.0 | 30 | 12 | G1×6G2×3G3×3 | 15.0% | 2.9 |
| July | 8.3 | 16 | 11 | G1×6G2×3G4×2 | 13.3% | 2.8 |
| August | 7.7 | 17 | 13 | G1×8G2×1G3×3G4×1 | 12.9% | 2.8 |
| September | 8.0 | 4 | 14 | G1×9G2×2G3×1G4×2 | 15.0% | 2.7 |
| October | 9.0 | 7 | 19 | G1×7G2×7G3×2G4×2G5×1 | 31.5% | 3.4 |
| November | 9.0 | 13 | 15 | G1×6G2×4G3×1G4×3G5×1 | 22.5% | 3.1 |
| December | 8.0 | 1 | 12 | G1×7G2×4G4×1 | 13.7% | 3.1 |
In the hall of storms: 13 November 1960 · Kp 9.0 →
All-time record: Kp 9.0 — reached on 27 days, most recently 2024-05-11.
Ranked from the data: peak Kp, then intervals spent at 9.0. Nicknames and reach notes only where documented.
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