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Solar flares in April 1999
C-class48
M-class5
X-class0
LargestM5.41999-04-04
Sunspot number92.9NOAA SWPC
Flares per day (C and above)
M/X flares per day
Same month a year earlier
| Month | C | M | X | Largest |
|---|---|---|---|---|
| April 1998 | 69 | 4 | 2 | X1.2 |
| April 1999 | 48 | 5 | 0 | M5.4 |
Top 15 flares
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 1999-04-04 | 05:15 | 05:25 | 15 | M5.4 | N18E72 | 8508 |
| 1999-04-03 | 22:56 | 23:10 | 23 | M4.3 | N29E81 | – |
| 1999-04-02 | 08:06 | 08:21 | 23 | M1.1 | – | – |
| 1999-04-08 | 16:07 | 16:13 | 10 | M1.1 | N23E18 | – |
| 1999-04-29 | 19:45 | 19:54 | 20 | M1.1 | N22W16 | – |
| 1999-04-30 | 12:10 | 12:21 | 15 | C8.2 | N24W17 | – |
| 1999-04-08 | 08:36 | 08:43 | 13 | C6.9 | N22E21 | 8508 |
| 1999-04-22 | 04:58 | 05:09 | 21 | C4.5 | – | – |
| 1999-04-30 | 03:50 | 03:55 | 8 | C4.2 | N22W15 | 8524 |
| 1999-04-28 | 20:27 | 20:32 | 8 | C3.8 | – | – |
| 1999-04-29 | 17:34 | 17:41 | 13 | C3.7 | N21W08 | 8524 |
| 1999-04-06 | 06:52 | 07:05 | 30 | C3.5 | N22E47 | 8508 |
| 1999-04-08 | 08:57 | 09:01 | 6 | C3.5 | N22E21 | 8508 |
| 1999-04-08 | 17:14 | 17:18 | 7 | C3.4 | N23E15 | 8508 |
| 1999-04-05 | 23:01 | 23:09 | 14 | C3.3 | S28W26 | 8506 |
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
53 flares of class C or larger in April 1999; by M/X count it ranks 315 of 565 months.