giovedì 19 ottobre 2017

Weekly Forecasts Bulletin

Solar activity forecast for the period October 20 - October 26, 2017


Activity level: mostly very low to low
X-ray background flux (1.0-8.0 A): in the range A3.5-A9.5
Radio flux (10.7 cm): a fluctuation in the range 66-80 f.u.
Events: class C (0-4/period), class M (0/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 0-50

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

Geomagnetic activity forecast for the period October 20 - October 26, 2017


Quiet: Oct 20 - 21
Unsettled: Oct 22 - 23, 26
Active:    Oct 24 - 26
Minor storm:  Oct 24 - 25
Major storm: 0
Severe storm: 0

Geomagnetic activity summary:
Coming weekend, we expect quiet to unsettled conditions till Monday,
October 23.
Between October 23 and 26, we expect active conditions arrival cused by
coronal hole HSS which can reach the minor storm level (October 24 - 25).
The last day (Thursday, October 26), we expect unsettled conditions
return.

Tomas Bayer
RWC Prague
Institute of Geophysics of the ASCR, Prague
Department of Geomagnetism
Budkov observatory (BDV)

Geomagnetic activity forecast for the period October 20 - November 15, 2017

Geomagnetic field will be:
quiet on October 20, 30 - 31, November (19)
quiet to unsettled on October 22, 28 - 29, November 1 - 6, 13 - 15
quiet to active on October 21,  23 - 27, November 7, 9 - 12
active to disturbed on November 8

Amplifications of the solar wind, mostly from coronal holes, are expected on October (22, 24,) 25 - 26, November 7 - 12

Remarks:
- Amplifications of the solar wind - prediction is less reliable at present.
- Parenthesis means lower probability of activity enhancement
and/or lower reliability of prediction.

F. K. Janda, OK1HH
Czech Propagation Interested Group
OK1HH compiling weekly forecasts since January 1978
e-mail: ok1hh(at)rsys.cz