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Geomagnetic activity in July 1940
Mean Ap11.7No. 604 of 1138
G1+ days7
G3+ days1
Max Ap5813 Jul 1940
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 3 Jul 1940 | 5o | 15 | G1 |
| 4 Jul 1940 | 5o | 22 | G1 |
| 10 Jul 1940 | 5o | 28 | G1 |
| 13 Jul 1940 | 8- | 58 | G4 |
| 14 Jul 1940 | 5- | 20 | G1 |
| 22 Jul 1940 | 5- | 14 | G1 |
| 30 Jul 1940 | 5- | 18 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| July 1939 | 19.0 | 14 | 4 |
| July 1940 | 11.7 | 7 | 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 11.7 in July 1940, No. 604 of 1138 months since 1932; 7 days reached G1 or higher.