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Geomagnetic activity in July 1991
Mean Ap27.2No. 40 of 1138
G1+ days16
G3+ days4
Max Ap13413 Jul 1991
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 3 Jul 1991 | 5- | 29 | G1 |
| 4 Jul 1991 | 5- | 13 | G1 |
| 8 Jul 1991 | 8o | 68 | G4 |
| 9 Jul 1991 | 8o | 117 | G4 |
| 10 Jul 1991 | 5o | 19 | G1 |
| 11 Jul 1991 | 5o | 20 | G1 |
| 12 Jul 1991 | 6- | 28 | G2 |
| 13 Jul 1991 | 9- | 134 | G5 |
| 14 Jul 1991 | 7- | 75 | G3 |
| 16 Jul 1991 | 5+ | 22 | G1 |
| 17 Jul 1991 | 6- | 41 | G2 |
| 18 Jul 1991 | 5- | 21 | G1 |
| 19 Jul 1991 | 6+ | 40 | G2 |
| 20 Jul 1991 | 5o | 28 | G1 |
| 21 Jul 1991 | 6- | 32 | G2 |
| 22 Jul 1991 | 5- | 23 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| July 1990 | 13.6 | 4 | 2 |
| July 1991 | 27.2 | 16 | 4 |
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 27.2 in July 1991, No. 40 of 1138 months since 1932; 16 days reached G1 or higher.