Why do fronts become stationary?
Fronts become stationary because the stationary front is like a stand-off between a cold front and a warm front. The warm front is trying to get on top of the warm front and make a warm front, while the cold front tried to avance on the warm front. Neither are successful, so they just stand there waiting for each other to move and one to become dominant. They stay where they are until one other front pushes them away.
