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Geomagnetic activity in July 1938
Mean Ap13.2No. 488 of 1138
G1+ days9
G3+ days1
Max Ap6715 Jul 1938
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Jul 1938 | 5- | 23 | G1 |
| 4 Jul 1938 | 6o | 35 | G2 |
| 5 Jul 1938 | 5- | 17 | G1 |
| 10 Jul 1938 | 5+ | 28 | G1 |
| 13 Jul 1938 | 5- | 12 | G1 |
| 14 Jul 1938 | 5+ | 19 | G1 |
| 15 Jul 1938 | 7o | 67 | G3 |
| 16 Jul 1938 | 5o | 31 | G1 |
| 30 Jul 1938 | 6o | 45 | G2 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| July 1937 | 12.2 | 9 | 0 |
| July 1938 | 13.2 | 9 | 1 |
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 13.2 in July 1938, No. 488 of 1138 months since 1932; 9 days reached G1 or higher.