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Geomagnetic activity in September 2018
Mean Ap9.0No. 847 of 1138
G1+ days3
G3+ days0
Max Ap3511 Sep 2018
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 10 Sep 2018 | 5o | 20 | G1 |
| 11 Sep 2018 | 6o | 35 | G2 |
| 22 Sep 2018 | 5- | 27 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| September 2017 | 18.1 | 11 | 3 |
| September 2018 | 9.0 | 3 | 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 9.0 in September 2018, No. 847 of 1138 months since 1932; 3 days reached G1 or higher.