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Geomagnetic activity in February 1940
Mean Ap12.4No. 550 of 1138
G1+ days3
G3+ days0
Max Ap391 Feb 1940
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Feb 1940 | 5o | 39 | G1 |
| 20 Feb 1940 | 5o | 21 | G1 |
| 25 Feb 1940 | 5o | 36 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| February 1939 | 15.2 | 6 | 2 |
| February 1940 | 12.4 | 3 | 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 12.4 in February 1940, No. 550 of 1138 months since 1932; 3 days reached G1 or higher.