Do you know about Coriolis?
One way to think about it:
1. say you have a low pressure spot in the northern hemisphere.
2. a parcel of air south of that spot will head north, toward the low pressure.
3. That parcel was moving east at the speed of the earth surface at that latitude.
4. As the parcel moves north, it is moving east relative to the ground because you are getting closer to the axis of rotation and the velocity of the ground decreases.
5. Now think about another parcel north of that low pressure spot.
6. That parcel is moving east slower than the earth to the south of it, so it falls behind to the west of the low pressure spot.
7. Now think about what we are looking at. we have a low pressure spot with air moving toward it from north falling to the west, and from the south .
8. That is a counterclockwise rotation around our low pressure spot, called "cyclonic". Usually it is just a gale, but if the pressure is low enough long enough it can be a hurricane or whatever you call a strong cyclone where you live.
9. South of the equator, all those directions are reversed of course, and the air spins clockwise around the low pressure spot.