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Geomagnetic activity in August 1939
Mean Ap19.0No. 180 of 1138
G1+ days9
G3+ days4
Max Ap13322 Aug 1939
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 10 Aug 1939 | 5- | 13 | G1 |
| 11 Aug 1939 | 6- | 16 | G2 |
| 12 Aug 1939 | 8- | 88 | G4 |
| 13 Aug 1939 | 6o | 34 | G2 |
| 16 Aug 1939 | 8- | 62 | G4 |
| 17 Aug 1939 | 5o | 20 | G1 |
| 19 Aug 1939 | 5- | 11 | G1 |
| 22 Aug 1939 | 8- | 133 | G4 |
| 23 Aug 1939 | 8- | 89 | G4 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| August 1938 | 12.4 | 8 | 2 |
| August 1939 | 19.0 | 9 | 4 |
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 19.0 in August 1939, No. 180 of 1138 months since 1932; 9 days reached G1 or higher.