Geomagnetic Storms of 1964
32 geomagnetic storms of G1 or more began in 1964: 16 G1, 12 G2, 3 G3, 1 G4, 0 G5. The strongest began September 22, 1964 and reached Kp 8-, rank 282 of every storm since 1932.
By month
Every storm of 1964
Times are UT, when the first block at Kp 5 or more began.
| Began (UTC) | Level | Peak Kp | Hours | Highest daily Ap |
|---|---|---|---|---|
| Jan 2, 03:00 | G3 Strong | 7- | 12 | 53 |
| Jan 16, 09:00 | G1 Minor | 5 | 9 | 27 |
| Jan 31, 09:00 | G1 Minor | 5 | 12 | 26 |
| Feb 6, 03:00 | G1 Minor | 5+ | 6 | 31 |
| Feb 8, 21:00 | G2 Moderate | 6- | 3 | 20 |
| Feb 13, 03:00 | G1 Minor | 5 | 9 | 32 |
| Feb 20, 21:00 | G1 Minor | 5+ | 3 | 18 |
| Feb 25, 18:00 | G2 Moderate | 6- | 3 | 19 |
| Mar 4, 03:00 | G2 Moderate | 6 | 24 | 52 |
| Mar 22, 12:00 | G2 Moderate | 6- | 9 | 28 |
| Mar 23, 09:00 | G2 Moderate | 6 | 3 | 30 |
| Mar 30, 15:00 | G2 Moderate | 6- | 3 | 26 |
| Apr 1, 15:00 | G3 Strong | 7+ | 12 | 46 |
| Apr 18, 12:00 | G1 Minor | 5 | 3 | 21 |
| Apr 27, 15:00 | G1 Minor | 5+ | 18 | 33 |
| Apr 29, 00:00 | G1 Minor | 5 | 3 | 16 |
| May 1, 00:00 | G2 Moderate | 6 | 3 | 23 |
| May 11, 00:00 | G1 Minor | 5+ | 6 | 19 |
| May 13, 18:00 | G1 Minor | 5+ | 3 | 18 |
| May 14, 12:00 | G2 Moderate | 6 | 21 | 28 |
| May 25, 06:00 | G2 Moderate | 6+ | 6 | 31 |
| Jun 10, 03:00 | G3 Strong | 7- | 12 | 49 |
| Jun 20, 12:00 | G1 Minor | 5 | 3 | 17 |
| Jul 17, 15:00 | G2 Moderate | 6- | 12 | 24 |
| Aug 4, 03:00 | G2 Moderate | 6+ | 6 | 34 |
| Sep 6, 21:00 | G1 Minor | 5 | 3 | 12 |
| Sep 7, 18:00 | G1 Minor | 5 | 3 | 28 |
| Sep 22, 00:00 | G4 Severe | 8- | 6 | 44 |
| Sep 28, 15:00 | G2 Moderate | 6- | 3 | 35 |
| Oct 4, 15:00 | G1 Minor | 5 | 6 | 30 |
| Oct 26, 06:00 | G1 Minor | 5+ | 3 | 18 |
| Dec 16, 12:00 | G1 Minor | 5+ | 3 | 15 |
More
Sources
Kp and ap from GFZ Helmholtz Centre for Geosciences, Geomagnetic Observatory Niemegk, licensed CC BY 4.0: Matzka, J., Stolle, C., Yamazaki, Y., Bronkalla, O. and Morschhauser, A., 2021, The geomagnetic Kp index and derived indices of geomagnetic activity, Space Weather, doi:10.1029/2020SW002641; data doi:10.5880/Kp.0001. Storms, levels and aurora reach worked out by WeatherOverTime from those values and NOAA’s space weather scales. Definitive through August 31, 2026; later values are preliminary. Rebuilt 2026-09-24.