Geomagnetic activity level | Quiet | Agitated | Active | Minor storm | Moderate storm | Intense storm | Severe storm | Extreme storm |
Kp | Kp < 27 | 27 ≤ Kp < 37 | 37 ≤ Kp < 47 | 47 ≤ Kp < 57 | 57 ≤ Kp < 67 | 67 ≤ Kp < 77 | 77 ≤ Kp < 87 | 87 ≤ Kp ≤ 90 |