Large coronal hole and future space weather event?

Solar magnetic fields usually come in pairs: active regions have two opposite polarities, similar to bar magnets. One can identify some of these bipolar structures in a solar magnetogram from GONG on the right with positive/negative polarity fields shown as white/black halftones. Sometimes, the patterns are more complex with multiple positive and negative polarities.  Magnetic flux in these twin or multi-polarity regions is usually well-balanced: magnetic field lines originating in one polarity connect to the opposite polarity in the same active region or its surroundings. Corona is bright above closed magnetic field areas (active regions, see SDO/AIA image on far right). There are, however, areas which have predominantly single polarity magnetic field. Magnetic field lines originating in these unipolar areas may not connect to the solar surface, but extend to the interplanetary space. These areas of opened magnetic field coincide with coronal holes, areas were the corona appears much darker. One of these large coronal holes is now crossing solar visible disk. Coronal holes are associated with streams of fast solar wind, which cause moderate geomagnetic storms. We should expect a moderate geomagnetic storm activity in several days after the corona hole passes solar central meridian.