Hvezdáreň Roztoky

May 21 – 27, 2021

Solar activity forecast for the period May 21 – 27, 2021

Issued: 2021 May 20 2100 UTC

Activity level from May 21 to May 24: very low to low
X-ray background flux (1.0-8.0 A): in the range A2.0-B2.0
Radio flux (10.7 cm): a fluctuation in the range 70-90 f.u.
Events: class C (0-2/day), class M (0/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 0-40

Activity level from May 25 to May 27: very low to low
X-ray background flux (1.0-8.0 A): in the range A2.0-B2.0
Radio flux (10.7 cm): a fluctuation in the range 70-90 f.u.
Events: class C (0-2/day), class M (0/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 0-40

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

Geomagnetic activity forecast for the period May 21 – 27, 2021

Issued: 2021 May 20 2130 UTC

Quiet: May 26 – 27
Quiet to unsettled: May 23 – 25
Quiet to active: May 21 – 22

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