Solar activity forecast for the period May 20 - May 21, 2026

Issued: 2026 May 19 17:00 UTC


Analysis from May 18/1700 UTC to May 19/1700 UTC:

Sunspot Regions on the Disk 19/1315 UTC (SDO Continuum): 5
The Largest Event: C2.1 from Region 4436 at 19/0740 UT
X-ray background flux (1.0-8.0 A) May 18: B3.3
Radio Flux 10.7 cm at 18/2300 UTC (Penticton): 104
Solar Wind Speed at 19/1645 UTC: 513.9 km/s, Density: 1.6 p/cm^3


Forecast:

activity level will be low
Event probabilities: Class C: 85, Class M: 30, Class X: 10, Proton: 05
X-ray background flux (1.0-8.0 A): in the range B3.0-B4.0
Radio Flux 10.7 cm: a fluctuation in the range 92-116

Karolína Knesplová
RWC Prague, Astronomical Institute, Solar Dept., Ondrejov, Czech Republic
e-mail: sunwatch(at)asu.cas.cz