Solar activity forecast for the period September 21 - 22, 2017


Issued: 2017 September 20 17:15 UTC


Analysis from September 19/1700 UTC to September 20/1700 UTC:

Sunspot Regions on the Disk 20/1623 UTC (SDO Continuum): 2
The Largest Event: B5.4 at 20/1243 UTC
X-ray background flux (1.0-8.0 A) September 19: invalid data
Radio Flux 10.7 cm at 19/2300 UTC (Penticton): 72
Solar Wind Speed at 20/1645 UTC: 435.8 km/s, Density: 3.8 p/cm^3


Forecast:
 
activity level will be very low
Event probabilities: Class C: 10, Class M: 01, Class X: 01, Proton: 01
X-ray background flux (1.0-8.0 A): in the range A4.5 - A9.5
Radio Flux 10.7 cm: a fluctuation in the range 67-78

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