April 16 – 22, 2021

Solar activity forecast for the period April 16 – 22, 2021

Issued: 2021 Apr 15 2100 UTC

Activity level from Apr 16 to Apr 19: mostly very low
X-ray background flux (1.0-8.0 A): in the range A0.0-A9.0
Radio flux (10.7 cm): a fluctuation in the range 70-85 f.u.
Events: class C (0-1/period), class M (0/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 0-35

Activity level from Apr 20 to Apr 22: mostly very low
X-ray background flux (1.0-8.0 A): in the range A0.0-A9.0
Radio flux (10.7 cm): a fluctuation in the range 70-85 f.u.
Events: class C (0-1/period), class M (0/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 0-35

Jozef Lesko
Roztoky Observatory, Slovak Republic
e-mail: safor (at) protonmail.ch

Geomagnetic activity forecast for the period April 16 – 22, 2021

Issued: 2021 Apr 15 2130 UTC

Quiet to unsettled: Apr 21 – 22
Quiet to active: Apr 16 – 20

Jozef Lesko
Roztoky Observatory, Slovak Republic
e-mail: safor (at) protonmail.ch