Automated forecasts of High Speed Solar wind streams (HSS) arriving at Earth. The forecast, made up to four days in advance, is based on coronal hole observations. The information of coronal hole areas is extracted from SDO/AIA 193 (images above) via histogram-based thresholding methods. For Earth-affecting HSS only areas of coronal holes within a slice of +/-7.5⁰, around the central meridian are taken into account.

The area is used to calculate solar wind and geomagnetic parameters at a distance of 1 AU (shown as blue crosses in panels below). Graphs present the total magnetic field strength B and southward component B_z (black and red line in top panel), the proton speed v (middle panel) and the related geomagnetic disturbances in the form of the Dst index (bottom).