Solar activity forecast for the period April 20 - 21, 2017


Issued: 2017 April 19 17:15 UTC


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

Sunspot Regions on the Disk 19/1623 UTC (SDO Continuum): 2
The Largest Event: C5.5 from Region 2651 at 18/2010 UTC
X-ray background flux (1.0-8.0 A) April 18: A9.7
Radio Flux 10.7 cm at 18/2300 UTC (Penticton): 86
Solar Wind Speed at 19/1644 UTC: 410.0 km/s, Density: 5.3 p/cm^3


Forecast:
 
activity level will be low to moderate
Event probabilities: Class C: 60, Class M: 20, Class X: 01, Proton: 01
X-ray background flux (1.0-8.0 A): in the range A8.0 - B2.5
Radio Flux 10.7 cm: a fluctuation in the range 76 - 96

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