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Geomagnetic activity in January 1940
Mean Ap14.9No. 362 of 1138
G1+ days11
G3+ days2
Max Ap473 Jan 1940
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 3 Jan 1940 | 8- | 47 | G4 |
| 4 Jan 1940 | 5o | 24 | G1 |
| 5 Jan 1940 | 5o | 12 | G1 |
| 7 Jan 1940 | 5o | 19 | G1 |
| 9 Jan 1940 | 5- | 12 | G1 |
| 10 Jan 1940 | 6- | 27 | G2 |
| 11 Jan 1940 | 5- | 23 | G1 |
| 12 Jan 1940 | 5o | 27 | G1 |
| 17 Jan 1940 | 5o | 21 | G1 |
| 18 Jan 1940 | 7- | 38 | G3 |
| 31 Jan 1940 | 5o | 29 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| January 1939 | 7.1 | 0 | 0 |
| January 1940 | 14.9 | 11 | 2 |
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.
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About this page
Mean Ap 14.9 in January 1940, No. 362 of 1138 months since 1932; 11 days reached G1 or higher.