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Solar flares in October 1999
C-class193
M-class8
X-class1
LargestX1.81999-10-14
Sunspot number167.7NOAA SWPC
Flares per day (C and above)
M/X flares per day
Same month a year earlier
| Month | C | M | X | Largest |
|---|---|---|---|---|
| October 1998 | 80 | 3 | 0 | M2.4 |
| October 1999 | 193 | 8 | 1 | X1.8 |
Top 15 flares
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 1999-10-14 | 08:54 | 09:00 | 9 | X1.8 | N11E32 | 8731 |
| 1999-10-26 | 21:09 | 21:25 | 28 | M3.7 | – | – |
| 1999-10-26 | 18:38 | 18:52 | 22 | M2.3 | S13W02 | 8739 |
| 1999-10-27 | 13:24 | 13:37 | 37 | M1.8 | S16W87 | 8737 |
| 1999-10-20 | 05:53 | 06:22 | 50 | M1.7 | N10W48 | 8731 |
| 1999-10-25 | 06:26 | 06:31 | 8 | M1.7 | S23E27 | 8741 |
| 1999-10-27 | 15:18 | 15:41 | 47 | M1.4 | – | – |
| 1999-10-26 | 07:27 | 07:45 | 44 | M1.2 | N09W20 | 8739 |
| 1999-10-27 | 09:08 | 09:12 | 8 | M1.0 | – | – |
| 1999-10-25 | 23:15 | 23:52 | 50 | C9.8 | S13E02 | – |
| 1999-10-19 | 19:26 | 19:41 | 27 | C8.7 | N17W50 | 8732 |
| 1999-10-01 | 00:08 | 00:17 | 12 | C7.7 | – | – |
| 1999-10-31 | 06:50 | 07:02 | 26 | C7.6 | S19E26 | 8749 |
| 1999-10-15 | 00:58 | 01:15 | 33 | C7.4 | – | 8731 |
| 1999-10-19 | 21:56 | 22:04 | 20 | C7.3 | N18W54 | 8732 |
All times UTC. Until June 2017 classes are NOAA's reports of the time (GOES-15 and earlier included a 0.7 scaling factor); later classes come from calibrated GOES-16/18 data, so the same flare reads about 1.4× larger. Do not compare the two periods directly.
← September 1999November 1999 →
About this page
202 flares of class C or larger in October 1999; by M/X count it ranks 254 of 565 months.