Solar Cycle 18 - Top 50 geomagnetic storms

On this page you will find an overview of the strongest geomagnetic storms from Solar Cycle 18 together with links to more information in our archive. The Kp-values on this page are the official, finalized Kp-values from the GFZ in Potsdam, Germany. Times are in UTC.

		Ap	Kp max	00-03h	03-06h	06-09h	09-12h	12-15h	15-18h	18-21h	21-00h
1	1946/09/22	198	9	4-	8+	8-	9-	9	8+	7	6
2	1946/07/27	152	9	9-	9-	9	7-	5+	4-	4-	2+
3	1946/03/28	213	9-	5	6	8+	9-	9-	9-	8+	8
4	1946/03/25	195	9-	8-	7+	7+	8-	8+	9-	8-	8-
5	1949/01/25	156	9-	9-	8	7-	4+	5	6	8+	8+
6	1949/05/12	153	9-	2	2	7+	7+	8+	9-	8+	7
7	1946/02/08	118	9-	9-	8-	7+	7	6-	6-	4	3
8	1946/04/23	117	9-	4-	4	5+	6	6+	8-	8-	9-
9	1947/04/17	100	9-	4-	4-	2-	2-	6+	7-	9-	8+
10	1951/10/28	98	9-	0+	4-	3+	5+	7	8	9-	5
11	1946/07/26	79	9-	4-	4	3	4-	3+	3+	9-	8
12	1950/02/20	79	9-	2+	3-	2-	2+	3	5	9-	8+
13	1951/09/26	73	9-	9-	8-	4+	4-	3-	3+	2+	3-
14	1949/10/15	156	8+	6	6	7+	8	7+	7+	8+	8-
15	1948/03/15	140	8+	6-	8+	8	7+	6+	7	8-	5
16	1950/08/19	136	8+	6-	4+	6-	6+	8	8+	8-	8
17	1947/03/03	128	8+	7	5	7-	7	6+	6-	8+	8
18	1946/02/07	127	8+	4-	2	4	8+	8-	8	7	8
19	1951/09/25	116	8+	4-	5-	5-	5+	7+	8-	8	8+
20	1950/08/20	108	8+	8+	8	8-	8-	4	3+	2+	2
21	1949/01/26	100	8+	8+	8	7	6-	5	5	5-	4
22	1946/04/24	99	8+	8+	7+	7-	6+	4+	7-	5-	3+
23	1952/04/21	94	8+	3-	3+	4	4	8+	8	7	6+
24	1944/04/02	88	8+	4+	5	8	8+	6	4	5	4
25	1948/10/18	86	8+	8+	7-	5+	4-	4-	4	5+	7+
26	1944/12/16	83	8+	4	4-	4+	6	8	8+	5	3
27	1947/08/22	71	8+	3-	4	5	8+	6+	6	5-	4+
28	1948/10/17	35	8+	1	0+	3+	1+	0+	0+	2+	8+
29	1946/09/23	146	8	7+	8-	8	6+	7	8	6	7-
30	1946/03/24	117	8	8	8-	5	6-	7+	8	3+	5+
31	1952/03/06	82	8	8	7+	6+	5-	4+	4	5	5+
32	1952/06/30	78	8	5+	8	8-	7	4-	2+	2-	2+
33	1952/05/27	72	8	8	6-	5-	5+	4+	5+	6-	5
34	1947/07/17	68	8	1	1-	1-	2	1+	7	8	8-
35	1949/05/13	59	8	8	7+	3+	2	5+	3+	1	2+
36	1951/06/17	38	8	2+	1+	2-	1	1-	5-	4+	8
37	1948/08/08	146	8-	5+	7-	7+	8-	8-	7	8-	8-
38	1946/09/18	136	8-	7+	7+	8-	7	7	7	7+	5
39	1947/09/25	100	8-	8-	7+	7+	6	6	6-	5	5-
40	1948/10/19	94	8-	7-	7+	8-	7+	5+	5+	4+	2+
41	1949/10/14	91	8-	4-	4+	5	6+	6-	7+	8-	7
42	1949/03/22	90	8-	7	8-	7-	7-	5-	6-	6-	3+
43	1947/03/08	90	8-	2	3+	5+	6-	8-	7+	7-	7
44	1951/07/02	82	8-	7+	8-	7-	6	4	5-	4	5-
45	1952/03/31	80	8-	8-	6	7-	5+	4	6	5+	5
46	1950/02/21	79	8-	7+	8-	6+	5-	5+	5-	4+	5-
47	1950/08/08	71	8-	8-	6+	8-	5	3+	3-	3-	4
48	1951/04/18	66	8-	1	1	4+	7	8-	6	5	5
49	1951/09/19	59	8-	3	2+	4-	4-	5+	8-	7	5-
50	1953/05/15	55	8-	1	3	3-	2+	5+	5+	8-	7-

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