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Geomagnetic storm on 25 Apr 1940 (G4)

Max Kp8oG4

Ap70No. 9 in 1940

Consecutive G1+ days2

Ap rank409since 1932

Kp by 3-hour slot (UTC)

00–035-

03–068o

06–094o

09–122-

12–152+

15–185o

18–217-

21–247-

The days around it

Date	Max Kp	Ap	Level
22 Apr 1940	5-	18	G1
23 Apr 1940	3o	8	–
24 Apr 1940	4-	8	–
25 Apr 1940	8o	70	G4
26 Apr 1940	7o	43	G3
27 Apr 1940	4-	10	–
28 Apr 1940	3-	8	–

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.

← 3 Apr 1940 26 Apr 1940 →

About this page

Max Kp 8o, Ap 70: No. 409 of 34,615 days since 1932 by Ap.