Aurora & Space WeatherHome › Geomagnetic history › 1999
Geomagnetic activity in February 1999
Mean Ap12.1No. 571 of 1138
G1+ days4
G3+ days1
Max Ap8018 Feb 1999
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 17 Feb 1999 | 5o | 17 | G1 |
| 18 Feb 1999 | 7- | 80 | G3 |
| 19 Feb 1999 | 6- | 40 | G2 |
| 28 Feb 1999 | 5+ | 17 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| February 1998 | 7.9 | 3 | 1 |
| February 1999 | 12.1 | 4 | 1 |
Dates and time slots are UTC. Kp is the 3-hourly planetary geomagnetic index (0–9); Ap is the daily average disturbance. G1–G5 follow the NOAA storm scale (Kp 5- and above counted as G1). Aurora visibility also depends on weather and location. The latest values are preliminary.
About this page
Mean Ap 12.1 in February 1999, No. 571 of 1138 months since 1932; 4 days reached G1 or higher.