In 1946 the planetary Kp peaked at 9.0 (G5) on 27 July 1946: 102 storm nights over the year, and 10.8% of its three-hour intervals at storm level.
| Month | Max Kp | Peak day | Storm nights | By class | At storm level | Avg Kp |
|---|---|---|---|---|---|---|
| January | 7.0 | 3 | 5 | G1×3G2×1G3×1 | 6.0% | 2.1 |
| February | 8.7 | 8 | 9 | G1×4G2×3G4×2 | 12.1% | 2.7 |
| March | 8.7 | 25 | 14 | G1×4G2×7G4×3 | 21.4% | 3.1 |
| April | 8.7 | 23 | 7 | G1×2G2×2G3×1G4×2 | 11.3% | 2.5 |
| May | 6.7 | 6 | 10 | G1×3G2×4G3×3 | 13.3% | 2.7 |
| June | 7.3 | 7 | 8 | G1×4G2×2G3×2 | 9.2% | 2.6 |
| July | 9.0 | 27 | 13 | G1×9G2×1G3×1G4×1G5×1 | 15.3% | 2.7 |
| August | 7.7 | 31 | 7 | G1×5G2×1G4×1 | 6.5% | 1.9 |
| September | 9.0 | 22 | 13 | G1×4G2×2G3×4G4×2G5×1 | 22.9% | 3.3 |
| October | 6.7 | 27 | 5 | G1×3G2×1G3×1 | 5.6% | 2.3 |
| November | 6.0 | 24 | 8 | G1×7G2×1 | 4.6% | 2.2 |
| December | 5.3 | 19 | 3 | G1×3 | 1.6% | 1.9 |
In the hall of storms: 27 July 1946 · 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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