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Monthly overview (Sep 2025)

The monthly mean values of the geomagnetic field components at Kakioka are D: -7°-58.7′°, H: 30122nT, Z: 36001nT and F: 46941nT for September 2025.

Monthly average of the K-index daily sum is 16.6. indicates a slightly high level of geomagnetic activity during the month.

Notable geomagnetic events include 3 magnetic storms, 1 si, 7 bay, 0 sfe, 4 pi and 4 pc.

The international 5 quietest days are the 7,19,20,21,27^th.

The international 5 most disturbed days are the 2,6,15,29,30^th.

Date	K-index daily sum	Geomagnetic activity	International 5 quietest days	International 5 quietest days	geomagnetic 1-minute value plot
1	16	moderately calm			plot
2	34	disturbed		○	plot
3	16	moderately calm			plot
4	15	moderately calm			plot
5	14	moderately calm			plot
6	24	disturbed		○	plot
7	3	extremely calm	○		plot
8	20	moderately disturbed			plot
9	19	moderately disturbed			plot
10	11	moderately calm			plot
11	14	moderately calm			plot
12	16	moderately calm			plot
13	9	calm			plot
14	19	moderately disturbed			plot
15	33	disturbed		○	plot
16	21	moderately disturbed			plot
17	17	moderately disturbed			plot
18	12	moderately calm			plot
19	1	extremely calm	○		plot
20	4	calm	○		plot
21	12	moderately calm	○		plot
22	23	disturbed			plot
23	20	moderately disturbed			plot
24	11	moderately calm			plot
25	13	moderately calm			plot
26	8	calm			plot
27	10	calm	○		plot
28	17	moderately disturbed			plot
29	30	disturbed		○	plot
30	35	disturbed		○	plot

*) Plot diagram opens in a separate window.