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Geomagnetic storm on 31 Mar 1940 (G4)

Max Kp8+G4

Ap128No. 4 in 1940

Consecutive G1+ days12

Ap rank84since 1932

Kp by 3-hour slot (UTC)

00–037o

03–065+

06–095-

09–128+

12–158o

15–188-

18–216o

21–246+

The days around it

Date	Max Kp	Ap	Level
28 Mar 1940	5+	21	G1
29 Mar 1940	8+	100	G4
30 Mar 1940	9-	189	G5
31 Mar 1940	8+	128	G4
1 Apr 1940	7-	66	G3
2 Apr 1940	7o	34	G3
3 Apr 1940	8o	98	G4

Highest-Ap days of 1940

30 Mar 1940189

24 Mar 1940187

25 Mar 1940184

31 Mar 1940128

25 Jun 1940126

29 Mar 1940100

3 Apr 194098

24 May 194078

25 Apr 194070

1 Apr 194066

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.

← 30 Mar 1940 1 Apr 1940 →

About this page

Max Kp 8+, Ap 128: No. 84 of 34,615 days since 1932 by Ap.