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Geomagnetic activity in April 1938
Mean Ap18.3No. 196 of 1138
G1+ days8
G3+ days3
Max Ap13616 Apr 1938
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 6 Apr 1938 | 5+ | 22 | G1 |
| 7 Apr 1938 | 5- | 19 | G1 |
| 11 Apr 1938 | 5- | 16 | G1 |
| 13 Apr 1938 | 7- | 36 | G3 |
| 14 Apr 1938 | 7o | 60 | G3 |
| 15 Apr 1938 | 5- | 19 | G1 |
| 16 Apr 1938 | 9o | 136 | G5 |
| 23 Apr 1938 | 6- | 41 | G2 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| April 1937 | 20.0 | 8 | 5 |
| April 1938 | 18.3 | 8 | 3 |
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 18.3 in April 1938, No. 196 of 1138 months since 1932; 8 days reached G1 or higher.