In a “normal” electrocardiogram (ECG), the transition of the QRS axis in the precordial leads occurs between leads V 3 and V 4 (i.e., there is a dominant S in V 3 and a dominant R in V 4).

Mike Moss: It is true that large scale low pressure systems in the Southern Hemisphere have winds that spiral into them in a clockwise manner, as opposed to the counterclockwise flow around lows in ...

Usually, tornadoes in the U.S. rotate counterclockwise. Coriolis force, imparted due to the Earth’s rotation, causes air around low centers to circulate counterclockwise in the northern hemisphere.