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Geomagnetic activity in May 1938
Mean Ap17.8No. 207 of 1138
G1+ days9
G3+ days3
Max Ap10311 May 1938
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 4 May 1938 | 7o | 44 | G3 |
| 11 May 1938 | 9- | 103 | G5 |
| 12 May 1938 | 7+ | 76 | G3 |
| 13 May 1938 | 6+ | 17 | G2 |
| 14 May 1938 | 6+ | 40 | G2 |
| 15 May 1938 | 5+ | 24 | G1 |
| 24 May 1938 | 5- | 16 | G1 |
| 28 May 1938 | 5- | 15 | G1 |
| 29 May 1938 | 6o | 38 | G2 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| May 1937 | 12.8 | 7 | 1 |
| May 1938 | 17.8 | 9 | 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 17.8 in May 1938, No. 207 of 1138 months since 1932; 9 days reached G1 or higher.