Solar Flare Watch2021: sunspot number and solar flux
| Month | Sunspot number | F10.7 flux |
|---|---|---|
| January | 11.1 | 76.1 |
| February | 8.4 | 73.6 |
| March | 17.0 | 75.2 |
| April | 24.8 | 74.7 |
| May | 20.0 | 75.6 |
| June | 24.4 | 79.8 |
| July | 35.9 | 81.0 |
| August | 22.8 | 77.9 |
| September | 51.9 | 87.4 |
| October | 36.6 | 90.3 |
| November | 36.0 | 86.9 |
| December | 69.4 | 102.9 |
About this page
Monthly sunspot number and 10.7 cm solar radio flux in 2021, from NOAA SWPC solar-cycle data.