In 1967 the planetary Kp peaked at 9.0 (G5) on 25 May 1967: 62 storm nights over the year, and 5.7% of its three-hour intervals at storm level.
| Month | Max Kp | Peak day | Storm nights | By class | At storm level | Avg Kp |
|---|---|---|---|---|---|---|
| January | 7.7 | 14 | 5 | G1×2G2×1G3×1G4×1 | 6.0% | 1.8 |
| February | 8.0 | 16 | 5 | G1×2G2×2G4×1 | 6.7% | 1.8 |
| March | 6.3 | 18 | 2 | G1×1G2×1 | 1.2% | 1.5 |
| April | 5.3 | 23 | 5 | G1×5 | 2.9% | 1.8 |
| May | 9.0 | 25 | 11 | G1×4G2×1G3×4G5×2 | 16.1% | 2.7 |
| June | 8.0 | 6 | 6 | G1×2G2×1G3×2G4×1 | 4.6% | 2.0 |
| July | 5.0 | 30 | 2 | G1×2 | 1.6% | 1.7 |
| August | 5.0 | 11 | 2 | G1×2 | 0.8% | 2.0 |
| September | 7.3 | 21 | 8 | G1×6G2×1G3×1 | 15.0% | 2.4 |
| October | 5.3 | 9 | 5 | G1×5 | 3.6% | 1.9 |
| November | 5.7 | 11 | 3 | G1×2G2×1 | 2.1% | 2.0 |
| December | 6.0 | 31 | 8 | G1×5G2×3 | 8.1% | 2.4 |
In the hall of storms: The near-war storm, 25 May 1967 · 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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