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Solar flares in August 1999
C-class182
M-class23
X-class2
LargestX1.41999-08-02
Sunspot number136.1NOAA SWPC
Flares per day (C and above)
M/X flares per day
Same month a year earlier
| Month | C | M | X | Largest |
|---|---|---|---|---|
| August 1998 | 122 | 14 | 5 | X4.9 |
| August 1999 | 182 | 23 | 2 | X1.4 |
Top 15 flares
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 1999-08-02 | 21:18 | 21:25 | 20 | X1.4 | S18W46 | 8647 |
| 1999-08-28 | 17:52 | 18:05 | 26 | X1.1 | S26W14 | 8674 |
| 1999-08-20 | 23:03 | 23:08 | 7 | M9.8 | S25E64 | 8674 |
| 1999-08-04 | 05:45 | 05:57 | 29 | M6.0 | S16W64 | 8647 |
| 1999-08-21 | 22:10 | 22:14 | 6 | M5.9 | S24E52 | 8674 |
| 1999-08-27 | 12:50 | 13:07 | 32 | M5.5 | S23W09 | 8674 |
| 1999-08-30 | 17:23 | 18:05 | 58 | M3.8 | – | 8674 |
| 1999-08-21 | 16:30 | 16:34 | 7 | M3.7 | S25E56 | 8674 |
| 1999-08-25 | 01:32 | 01:36 | 8 | M3.6 | S28E21 | 8674 |
| 1999-08-27 | 01:22 | 01:37 | 29 | M3.0 | – | – |
| 1999-08-27 | 16:23 | 16:36 | 44 | M3.0 | S31E04 | 8674 |
| 1999-08-28 | 00:50 | 01:02 | 26 | M2.8 | S26W16 | 8674 |
| 1999-08-05 | 15:55 | 16:23 | 38 | M1.9 | S31W69 | 8645 |
| 1999-08-02 | 00:23 | 00:27 | 7 | M1.8 | – | – |
| 1999-08-06 | 16:28 | 16:36 | 17 | M1.8 | S30W85 | 8645 |
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
207 flares of class C or larger in August 1999; by M/X count it ranks 130 of 565 months.