(a) Map of south-western Europe with Spain and Portugal borders. (b) High-resolution ground-based GNSS ROTI observations over this region for 21:30 UT on 23 April 2023. (c–d) GNSS ROTI keograms representing spatio‐temporal signatures of storm‐induced plasma disturbances at two different longitudes (4°E and 8°E) in south-western Europe on 23–24 April 2023. White/blank cells at the bottom are due to the data absence. The location of the El Arenosillo digisonde station in southern Spain is shown as a blue asterisk on map (a).