EUVI-A 195 Å running-ratio images showing the onset of the three flares (a), b), and c)) and their associated EUV waves (d), e), and f)). In a) the epipolar line shown in Fig. 1a is drawn as a long white arrow, and the solar limb is drawn as a dashed white line. The small white arrow in all images points to the tornado site. The dot-dashed/dashed lines in b) mark the positions of time series shown in Fig. 4, and the orange dashed line along the EUV wave front in e) is the position of the time series in Fig. 3.