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Solar flares in September 2017
C-class111
M-class33
X-class6
LargestX14.62017-09-06
Sunspot number42.3NOAA SWPC
Flares per day (C and above)
M/X flares per day
Same month a year earlier
| Month | C | M | X | Largest |
|---|---|---|---|---|
| September 2016 | 8 | 0 | 0 | C5.6 |
| September 2017 | 111 | 33 | 6 | X14.6 |
Top 15 flares
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 2017-09-06 | 11:52 | 12:02 | 18 | X14.6 | – | – |
| 2017-09-10 | 15:34 | 16:06 | 57 | X12.9 | – | – |
| 2017-09-06 | 08:52 | 09:10 | 25 | X3.2 | – | – |
| 2017-09-07 | 14:15 | 14:36 | 40 | X2.1 | – | – |
| 2017-09-07 | 10:14 | 10:15 | 4 | X1.2 | – | – |
| 2017-09-08 | 07:39 | 07:49 | 19 | X1.2 | – | – |
| 2017-09-04 | 20:22 | 20:33 | 16 | M8.4 | – | – |
| 2017-09-05 | 01:02 | 01:08 | 9 | M6.4 | – | – |
| 2017-09-07 | 23:50 | 23:59 | 24 | M6.0 | – | – |
| 2017-09-05 | 06:33 | 06:40 | 10 | M5.8 | – | – |
| 2017-09-09 | 10:46 | 11:04 | – | M5.8 | – | – |
| 2017-09-05 | 04:27 | 04:53 | 41 | M5.0 | – | – |
| 2017-09-08 | 15:03 | 15:47 | 61 | M4.6 | – | – |
| 2017-09-09 | 11:19 | 11:26 | 15 | M4.6 | – | – |
| 2017-09-06 | 15:51 | 15:56 | 13 | M4.0 | – | – |
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.
About this page
150 flares of class C or larger in September 2017; by M/X count it ranks 74 of 565 months.