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Geomagnetic activity in August 1940
Mean Ap10.8No. 683 of 1138
G1+ days4
G3+ days0
Max Ap389 Aug 1940
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 2 Aug 1940 | 5+ | 12 | G1 |
| 3 Aug 1940 | 6+ | 35 | G2 |
| 9 Aug 1940 | 6+ | 38 | G2 |
| 26 Aug 1940 | 6- | 19 | G2 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| August 1939 | 19.0 | 9 | 4 |
| August 1940 | 10.8 | 4 | 0 |
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 10.8 in August 1940, No. 683 of 1138 months since 1932; 4 days reached G1 or higher.