This study is devoted to HF radio wave propagation in the ionosphere during the May 1–3, 2010 geomagnetic storm. The research results were obtained by using two models, namely, the GSM TIP environment model developed at WD IZMIRAN and the radio-wave propagation model developed at I. Kant BFU. For certain selected frequencies we show the effect of the geomagnetic storm on the radio wave propagation. We give examples of a HF radio-wave path in the channels between the F1 and F2 layers of a high-latitude ionosphere and the F2 and F3 layers of a lowlatitude ionosphere. Characteristics of these layers may significantly affect the interpretation of the oblique sounding ionograms.