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Geomagnetic activity in February 1991
Mean Ap10.5No. 710 of 1138
G1+ days2
G3+ days0
Max Ap281 Feb 1991
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Feb 1991 | 6- | 28 | G2 |
| 2 Feb 1991 | 5o | 12 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| February 1990 | 22.9 | 18 | 2 |
| February 1991 | 10.5 | 2 | 0 |
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 10.5 in February 1991, No. 710 of 1138 months since 1932; 2 days reached G1 or higher.