Geomagnetic Storms of 1998
37 geomagnetic storms of G1 or more began in 1998: 18 G1, 8 G2, 7 G3, 3 G4, 1 G5. The strongest began May 2, 1998 and reached Kp 9-, rank 42 of every storm since 1932.
By month
Every storm of 1998
Times are UT, when the first block at Kp 5 or more began.
| Began (UTC) | Level | Peak Kp | Hours | Highest daily Ap |
|---|---|---|---|---|
| Jan 7, 00:00 | G2 Moderate | 6+ | 6 | 28 |
| Feb 17, 21:00 | G3 Strong | 7- | 9 | 36 |
| Feb 28, 21:00 | G1 Minor | 5 | 3 | 15 |
| Mar 10, 09:00 | G3 Strong | 7+ | 24 | 53 |
| Mar 15, 00:00 | G1 Minor | 5 | 3 | 20 |
| Mar 21, 12:00 | G2 Moderate | 6+ | 9 | 35 |
| Apr 23, 18:00 | G2 Moderate | 6- | 15 | 35 |
| Apr 25, 00:00 | G1 Minor | 5 | 3 | 26 |
| Apr 25, 18:00 | G1 Minor | 5 | 3 | 26 |
| Apr 26, 12:00 | G1 Minor | 5 | 3 | 31 |
| May 2, 03:00 | G5 Extreme | 9- | 60 | 101 |
| May 5, 03:00 | G3 Strong | 7- | 15 | 42 |
| May 17, 00:00 | G1 Minor | 5 | 3 | 12 |
| May 29, 15:00 | G3 Strong | 7- | 3 | 26 |
| Jun 26, 00:00 | G2 Moderate | 6+ | 9 | 42 |
| Jul 6, 12:00 | G1 Minor | 5 | 3 | 19 |
| Jul 16, 03:00 | G2 Moderate | 6 | 15 | 37 |
| Jul 23, 03:00 | G1 Minor | 5+ | 15 | 40 |
| Jul 24, 09:00 | G1 Minor | 5 | 3 | 28 |
| Jul 30, 21:00 | G1 Minor | 5 | 3 | 11 |
| Jul 31, 18:00 | G1 Minor | 5 | 3 | 29 |
| Aug 1, 18:00 | G2 Moderate | 6- | 3 | 21 |
| Aug 6, 06:00 | G3 Strong | 7+ | 24 | 64 |
| Aug 26, 09:00 | G4 Severe | 8 | 45 | 144 |
| Aug 29, 18:00 | G1 Minor | 5+ | 3 | 20 |
| Sep 18, 12:00 | G1 Minor | 5+ | 9 | 25 |
| Sep 24, 21:00 | G4 Severe | 8+ | 21 | 117 |
| Oct 1, 00:00 | G1 Minor | 5+ | 3 | 24 |
| Oct 2, 18:00 | G1 Minor | 5+ | 3 | 32 |
| Oct 7, 15:00 | G2 Moderate | 6- | 6 | 28 |
| Oct 19, 00:00 | G3 Strong | 7- | 21 | 62 |
| Oct 20, 18:00 | G1 Minor | 5 | 6 | 23 |
| Nov 7, 12:00 | G4 Severe | 8- | 21 | 66 |
| Nov 9, 03:00 | G3 Strong | 7- | 18 | 75 |
| Nov 13, 00:00 | G2 Moderate | 6 | 39 | 64 |
| Dec 11, 06:00 | G1 Minor | 5+ | 3 | 33 |
| Dec 29, 18:00 | G1 Minor | 5 | 3 | 22 |
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.