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Geomagnetic activity in April 2021
Mean Ap8.5No. 893 of 1138
G1+ days4
G3+ days0
Max Ap2817 Apr 2021
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 15 Apr 2021 | 5- | 12 | G1 |
| 16 Apr 2021 | 5o | 19 | G1 |
| 17 Apr 2021 | 5- | 28 | G1 |
| 25 Apr 2021 | 5o | 18 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| April 2020 | 5.3 | 1 | 0 |
| April 2021 | 8.5 | 4 | 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 8.5 in April 2021, No. 893 of 1138 months since 1932; 4 days reached G1 or higher.