Ray Dwayne Johnson (Fast & Furious 6) is a rescue-chopper pilot and he witnesses a massive earthquake on the San Andreas Fault line and this is going to have effects all the way to the Eastern coast of New York etc.
This is where fact separates from the silver screen as the San Andreas fault is a slip fault and the Western side would move in a NW direction. The effects of a force 9 quake on this area would be catastrophic and the SFX in the trailer show this admirably. But to have this effect all across the states of the US is highly unlikely, as there have been earthquakes of this magnitude before and they stay mainly localised. Also there are two mountain ranges running North-South (The Rocky Mountains and the Appalachian Mountains) to absorb any P or S Waves. The S waves being the ones that cause the surface damage. Whereas P waves penetrate through the ground and travel at different speeds depending on the medium it is passing through but travels faster than the S waves thus giving the warning of the devastation to come. But for an earthquake to travel 2,745 miles is fantasy as this film is, but hey there is nothing wrong with an epic disaster movie (Go the Rock, see what I did there (Rock)).
What the film could have done is the more likely result of the massive quake is that when the fault travels NW, this would create a humongous Mega-tsunami that would travel on the seabed until it hit Hawaii some 2400 miles away, Japan 5355 miles away and Australia 8,128 miles away and the only warning would be as the wave hit. We all remember the scene from Deep Impact (1998). We know this can happen as it was Hawaii that lost some of its coast way back in history but the evidence for the tsunami is still present high above the coast of west America.
But this is Dwayne Johnson, a hero and that’s what we like, turn off brain, grab the popcorn and enjoy.