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Monthly overview (Apr 1991)

The monthly mean values of the geomagnetic field components at Kakioka are D: -6°-51.2′°, H: 30131nT, Z: 34984nT and F: 46171nT for April 1991.

Monthly average of the K-index daily sum is 17.1. indicates a high level of geomagnetic activity during the month.

Notable geomagnetic events include 1 magnetic storms, 3 si, 0 bay, 1 sfe, 0 pi and 0 pc.

The international 5 quietest days are the 8,11,13,16,20^th.

The international 5 most disturbed days are the 3,4,28,29,30^th.

Date	K-index daily sum	Geomagnetic activity	International 5 quietest days	International 5 quietest days	geomagnetic 1-minute value plot
1	25	disturbed			plot
2	26	disturbed			plot
3	28	disturbed		○	plot
4	32	disturbed		○	plot
5	18	moderately disturbed			plot
6	14	moderately calm			plot
7	12	moderately calm			plot
8	09	calm	○		plot
9	15	moderately calm			plot
10	17	moderately disturbed			plot
11	09	calm	○		plot
12	18	moderately disturbed			plot
13	09	calm	○		plot
14	12	moderately calm			plot
15	08	calm			plot
16	07	calm	○		plot
17	17	moderately disturbed			plot
18	18	moderately disturbed			plot
19	18	moderately disturbed			plot
20	06	calm	○		plot
21	12	moderately calm			plot
22	16	moderately calm			plot
23	14	moderately calm			plot
24	17	moderately disturbed			plot
25	21	moderately disturbed			plot
26	16	moderately calm			plot
27	20	moderately disturbed			plot
28	23	disturbed		○	plot
29	31	disturbed		○	plot
30	26	disturbed		○	plot

*) Plot diagram opens in a separate window.