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We investigate the case of disagreement between predicted and observed in-situ parameters of the recurrent high-speed solar wind streams (HSSs) existing for Carrington rotation (CR) 2118 (December 2011) in comparison with CRs 2117 and 2119. The HSSs originated at the Sun from a recurrent polar coronal hole (CH) expanding to mid-latitudes, and its area in the central part of the solar disk increased with the rotation number. This part of the CH was responsible for the equatorial flank of the HSS directed to the Earth. The time and speed of arrival for this part of the HSS to the Earth were predicted by the hierarchical empirical model based on EUV-imaging and the Wang-Sheeley-Arge ENLIL semi-empirical replace model and compared with the parameters measured in-situ by model. The predicted parameters were compared with those measured in-situ. It was found, that for CR 2117 and CR 2119, the predicted HSS speed values agreed with the measured ones within the typical accuracy of ±100 km s−1. During CR 2118, the measured speed was on 217 km s−1 less than the value predicted in accordance with the increased area of the CH. We suppose that at CR 2118, the HSS overtook and interacted with complex ejecta formed from three merged coronal mass ejections (CMEs) with a mean speed about 400 km s−1. According to simulations of the Drag-based model, this complex ejecta might be created by several CMEs starting from the Sun in the period between 25 and 27 December 2011 and arriving to the Earth simultaneously with the HSS. Due to its higher density and magnetic field strength, the complex ejecta became an obstacle for the equatorial flank of the HSS and slowed it down. During CR 2117 and CR 2119, the CMEs appeared before the arrival of the HSSs, so the CMEs did not influence on the HSSs kinematics.

The origins of the solar wind and the interplanetary magnetic field sector structure in the beginning of the magnetic polarity reversal of 24th solar cycle were investigated using the Wilcox Solar Observatory magnetic field measurements and their products as well as the solar wind data from ACE and the SDO/AIA EUV images. The dominance of the quadrupole harmonics in the solar magnetic field in this period resulted in a four-sector structure of the interplanetary magnetic field. The dominating source of recurrent high-speed solar wind stream was a large trans-equatorial coronal hole of negative polarity evolving in the course of the polarity reversal process. The contribution of ICMEs to the high-speed solar wind did not exceed 17% of the total flux. The solar wind density flux averaged over the year amounted to 1 × 108 cm−2 s−1 which is considerably lower than the typical long-term value (2–4 × 108 cm−2 s−1 ). The slow-speed component of solar wind density flux constituted in average more than 68% of the total flux, the high-speed component was about 10%, reaching the maximum of 32% in some Carrington rotations.